Migrate spelling-0.0.21 changes from main

The titlebars are all the wrong size. I can't make it as tall as the XAML titlebar, cause of course not. I can't get dragging to work, cause I probably commented out the load bearing part of the code. The Transparent hole I thought I made? Not transparent at all. Probably b/c I'm setting Titlebar().Background() which goes behind the hole, when I want instead a Border w/in the TitlebarControl that the BG should be applied to.

It's a disaster.

.github/actions/spelling/README.md

@@ -0,0 +1,15 @@
+# check-spelling/check-spelling configuration
+
+File | Purpose | Format | Info
+-|-|-|-
+[allow/*.txt](allow/) | Add words to the dictionary | one word per line (only letters and `'`s allowed) | [allow](https://github.com/check-spelling/check-spelling/wiki/Configuration#allow)
+[reject.txt](reject.txt) | Remove words from the dictionary (after allow) | grep pattern matching whole dictionary words | [reject](https://github.com/check-spelling/check-spelling/wiki/Configuration-Examples%3A-reject)
+[excludes.txt](excludes.txt) | Files to ignore entirely | perl regular expression | [excludes](https://github.com/check-spelling/check-spelling/wiki/Configuration-Examples%3A-excludes)
+[patterns/*.txt](patterns/) | Patterns to ignore from checked lines | perl regular expression (order matters, first match wins) | [patterns](https://github.com/check-spelling/check-spelling/wiki/Configuration-Examples%3A-patterns)
+[candidate.patterns](candidate.patterns) | Patterns that might be worth adding to [patterns.txt](patterns.txt) | perl regular expression with optional comment block introductions (all matches will be suggested) | [candidates](https://github.com/check-spelling/check-spelling/wiki/Feature:-Suggest-patterns)
+[line_forbidden.patterns](line_forbidden.patterns) | Patterns to flag in checked lines | perl regular expression (order matters, first match wins) | [patterns](https://github.com/check-spelling/check-spelling/wiki/Configuration-Examples%3A-patterns)
+[expect/*.txt](expect.txt) | Expected words that aren't in the dictionary | one word per line (sorted, alphabetically) | [expect](https://github.com/check-spelling/check-spelling/wiki/Configuration#expect)
+[advice.md](advice.md) | Supplement for GitHub comment when unrecognized words are found | GitHub Markdown | [advice](https://github.com/check-spelling/check-spelling/wiki/Configuration-Examples%3A-advice)
+
+Note: you can replace any of these files with a directory by the same name (minus the suffix)
+and then include multiple files inside that directory (with that suffix) to merge multiple files together.

.github/actions/spelling/advice.md

@@ -1,4 +1,4 @@
-<!-- markdownlint-disable MD033 MD041 -->
+<!-- See https://github.com/check-spelling/check-spelling/wiki/Configuration-Examples%3A-advice --> <!-- markdownlint-disable MD033 MD041 -->
 <details>
 <summary>
 :pencil2: Contributor please read this
@@ -6,7 +6,7 @@
 
 By default the command suggestion will generate a file named based on your commit. That's generally ok as long as you add the file to your commit. Someone can reorganize it later.
 
-:warning: The command is written for posix shells. You can copy the contents of each `perl` command excluding the outer `'` marks and dropping any `'"`/`"'` quotation mark pairs into a file and then run `perl file.pl` from the root of the repository to run the code. Alternatively, you can manually insert the items...
+:warning: The command is written for posix shells. If it doesn't work for you, you can manually _add_ (one word per line) / _remove_ items to `expect.txt` and the `excludes.txt` files.
 
 If the listed items are:
 
@@ -20,31 +20,29 @@ See the `README.md` in each directory for more information.
 
 :microscope: You can test your commits **without** *appending* to a PR by creating a new branch with that extra change and pushing it to your fork. The [check-spelling](https://github.com/marketplace/actions/check-spelling) action will run in response to your **push** -- it doesn't require an open pull request. By using such a branch, you can limit the number of typos your peers see you make. :wink:
 
-<details><summary>:clamp: If you see a bunch of garbage</summary>
 
-If it relates to a ...
-<details><summary>well-formed pattern</summary>
+<details><summary>If the flagged items are :exploding_head: false positives</summary>
 
-See if there's a [pattern](https://github.com/check-spelling/check-spelling/wiki/Configuration-Examples:-patterns) that would match it.
+If items relate to a ...
+* binary file (or some other file you wouldn't want to check at all).
 
-If not, try writing one and adding it to a `patterns/{file}.txt`.
+  Please add a file path to the `excludes.txt` file matching the containing file.
 
-Patterns are Perl 5 Regular Expressions - you can [test](
-https://www.regexplanet.com/advanced/perl/) yours before committing to verify it will match your lines.
-
-Note that patterns can't match multiline strings.
-</details>
-<details><summary>binary-ish string</summary>
-
-Please add a file path to the `excludes.txt` file instead of just accepting the garbage.
-
-File paths are Perl 5 Regular Expressions - you can [test](
+  File paths are Perl 5 Regular Expressions - you can [test](
 https://www.regexplanet.com/advanced/perl/) yours before committing to verify it will match your files.
 
-`^` refers to the file's path from the root of the repository, so `^README\.md$` would exclude [README.md](
+  `^` refers to the file's path from the root of the repository, so `^README\.md$` would exclude [README.md](
 ../tree/HEAD/README.md) (on whichever branch you're using).
-</details>
-
+
+* well-formed pattern.
+
+  If you can write a [pattern](https://github.com/check-spelling/check-spelling/wiki/Configuration-Examples:-patterns) that would match it,
+  try adding it to the `patterns.txt` file.
+
+  Patterns are Perl 5 Regular Expressions - you can [test](
+https://www.regexplanet.com/advanced/perl/) yours before committing to verify it will match your lines.
+
+  Note that patterns can't match multiline strings.
 </details>
 
 </details>

.github/actions/spelling/allow/allow.txt

@@ -1,20 +1,21 @@
 admins
-apc
+allcolors
 Apc
-bsd
+apc
 breadcrumb
 breadcrumbs
+bsd
 calt
-CMMI
 ccmp
 changelog
 clickable
 clig
+CMMI
 copyable
 cybersecurity
 dalet
-dcs
 Dcs
+dcs
 dialytika
 dje
 downside
@@ -26,36 +27,43 @@ EDDC
 Enum'd
 Fitt
 formattings
+FTCS
 ftp
 fvar
+gantt
 gcc
 geeksforgeeks
 ghe
+github
 gje
 godbolt
 hostname
 hostnames
+https
 hyperlink
 hyperlinking
 hyperlinks
+iconify
 img
 inlined
 It'd
 kje
 libfuzzer
+libuv
 liga
 lje
 Llast
 llvm
 Lmid
 locl
+lol
 lorem
 Lorigin
 maxed
+minimalistic
 mkmk
 mnt
 mru
-noreply
 nje
 noreply
 ogonek
@@ -76,13 +84,16 @@ runtimes
 shcha
 slnt
 Sos
+ssh
 timeline
 timelines
 timestamped
 TLDR
 tokenizes
 tonos
+toolset
 tshe
+ubuntu
 uiatextrange
 UIs
 und
@@ -91,6 +102,7 @@ versioned
 vsdevcmd
 We'd
 wildcards
+XBox
+YBox
 yeru
 zhe
-allcolors

.github/actions/spelling/allow/apis.txt

@@ -5,6 +5,7 @@ aclapi
 alignas
 alignof
 APPLYTOSUBMENUS
+appxrecipe
 bitfield
 bitfields
 BUILDBRANCH
@@ -14,6 +15,7 @@ BYCOMMAND
 BYPOSITION
 charconv
 CLASSNOTAVAILABLE
+CLOSEAPP
 cmdletbinding
 COLORPROPERTY
 colspan
@@ -28,9 +30,14 @@ dataobject
 dcomp
 DERR
 dlldata
+DNE
 DONTADDTORECENT
+DWMSBT
+DWMWA
+DWMWA
 DWORDLONG
 endfor
+ENDSESSION
 enumset
 environstrings
 EXPCMDFLAGS
@@ -70,6 +77,7 @@ IDirect
 IExplorer
 IFACEMETHOD
 IFile
+IGraphics
 IInheritable
 IMap
 IMonarch
@@ -84,6 +92,7 @@ istream
 IStringable
 ITab
 ITaskbar
+itow
 IUri
 IVirtual
 KEYSELECT
@@ -95,12 +104,15 @@ lround
 Lsa
 lsass
 LSHIFT
+LTGRAY
+MAINWINDOW
 memchr
 memicmp
 MENUCOMMAND
 MENUDATA
-MENUITEMINFOW
 MENUINFO
+MENUITEMINFOW
+mmeapi
 MOUSELEAVE
 mov
 mptt
@@ -136,16 +148,18 @@ OUTLINETEXTMETRICW
 overridable
 PACL
 PAGESCROLL
+PATINVERT
 PEXPLICIT
 PICKFOLDERS
 pmr
 ptstr
+QUERYENDSESSION
 rcx
 REGCLS
 RETURNCMD
 rfind
-roundf
 ROOTOWNER
+roundf
 RSHIFT
 SACL
 schandle
@@ -175,6 +189,8 @@ Stubless
 Subheader
 Subpage
 syscall
+SYSTEMBACKDROP
+TABROW
 TASKBARCREATED
 TBPF
 THEMECHANGED
@@ -194,6 +210,8 @@ UOI
 UPDATEINIFILE
 userenv
 USEROBJECTFLAGS
+Viewbox
+virtualalloc
 wcsstr
 wcstoui
 winmain

.github/actions/spelling/allow/names.txt

@@ -69,6 +69,8 @@ Rincewind
 rprichard
 Schoonover
 shadertoy
+Shomnipotence
+simioni
 Somuah
 sonph
 sonpham

.github/actions/spelling/candidate.patterns

@@ -0,0 +1,523 @@
+# marker to ignore all code on line
+^.*/\* #no-spell-check-line \*/.*$
+# marker for ignoring a comment to the end of the line
+// #no-spell-check.*$
+
+# patch hunk comments
+^\@\@ -\d+(?:,\d+|) \+\d+(?:,\d+|) \@\@ .*
+# git index header
+index [0-9a-z]{7,40}\.\.[0-9a-z]{7,40}
+
+# cid urls
+(['"])cid:.*?\g{-1}
+
+# data url in parens
+\(data:[^)]*?(?:[A-Z]{3,}|[A-Z][a-z]{2,}|[a-z]{3,})[^)]*\)
+# data url in quotes
+([`'"])data:.*?(?:[A-Z]{3,}|[A-Z][a-z]{2,}|[a-z]{3,}).*\g{-1}
+# data url
+data:[-a-zA-Z=;:/0-9+]*,\S*
+
+# mailto urls
+mailto:[-a-zA-Z=;:/?%&0-9+@.]{3,}
+
+# magnet urls
+magnet:[?=:\w]+
+
+# magnet urls
+"magnet:[^"]+"
+
+# obs:
+"obs:[^"]*"
+
+# The `\b` here means a break, it's the fancy way to handle urls, but it makes things harder to read
+# In this examples content, I'm using a number of different ways to match things to show various approaches
+# asciinema
+\basciinema\.org/a/[0-9a-zA-Z]+
+
+# apple
+\bdeveloper\.apple\.com/[-\w?=/]+
+# Apple music
+\bembed\.music\.apple\.com/fr/playlist/usr-share/[-\w.]+
+
+# appveyor api
+\bci\.appveyor\.com/api/projects/status/[0-9a-z]+
+# appveyor project
+\bci\.appveyor\.com/project/(?:[^/\s"]*/){2}builds?/\d+/job/[0-9a-z]+
+
+# Amazon
+
+# Amazon
+\bamazon\.com/[-\w]+/(?:dp/[0-9A-Z]+|)
+# AWS S3
+\b\w*\.s3[^.]*\.amazonaws\.com/[-\w/&#%_?:=]*
+# AWS execute-api
+\b[0-9a-z]{10}\.execute-api\.[-0-9a-z]+\.amazonaws\.com\b
+# AWS ELB
+\b\w+\.[-0-9a-z]+\.elb\.amazonaws\.com\b
+# AWS SNS
+\bsns\.[-0-9a-z]+.amazonaws\.com/[-\w/&#%_?:=]*
+# AWS VPC
+vpc-\w+
+
+# While you could try to match `http://` and `https://` by using `s?` in `https?://`, sometimes there
+# YouTube url
+\b(?:(?:www\.|)youtube\.com|youtu.be)/(?:channel/|embed/|user/|playlist\?list=|watch\?v=|v/|)[-a-zA-Z0-9?&=_%]*
+# YouTube music
+\bmusic\.youtube\.com/youtubei/v1/browse(?:[?&]\w+=[-a-zA-Z0-9?&=_]*)
+# YouTube tag
+<\s*youtube\s+id=['"][-a-zA-Z0-9?_]*['"]
+# YouTube image
+\bimg\.youtube\.com/vi/[-a-zA-Z0-9?&=_]*
+# Google Accounts
+\baccounts.google.com/[-_/?=.:;+%&0-9a-zA-Z]*
+# Google Analytics
+\bgoogle-analytics\.com/collect.[-0-9a-zA-Z?%=&_.~]*
+# Google APIs
+\bgoogleapis\.(?:com|dev)/[a-z]+/(?:v\d+/|)[a-z]+/[-@:./?=\w+|&]+
+# Google Storage
+\b[-a-zA-Z0-9.]*\bstorage\d*\.googleapis\.com(?:/\S*|)
+# Google Calendar
+\bcalendar\.google\.com/calendar(?:/u/\d+|)/embed\?src=[@./?=\w&%]+
+\w+\@group\.calendar\.google\.com\b
+# Google DataStudio
+\bdatastudio\.google\.com/(?:(?:c/|)u/\d+/|)(?:embed/|)(?:open|reporting|datasources|s)/[-0-9a-zA-Z]+(?:/page/[-0-9a-zA-Z]+|)
+# The leading `/` here is as opposed to the `\b` above
+# ... a short way to match `https://` or `http://` since most urls have one of those prefixes
+# Google Docs
+/docs\.google\.com/[a-z]+/(?:ccc\?key=\w+|(?:u/\d+|d/(?:e/|)[0-9a-zA-Z_-]+/)?(?:edit\?[-\w=#.]*|/\?[\w=&]*|))
+# Google Drive
+\bdrive\.google\.com/(?:file/d/|open)[-0-9a-zA-Z_?=]*
+# Google Groups
+\bgroups\.google\.com/(?:(?:forum/#!|d/)(?:msg|topics?|searchin)|a)/[^/\s"]+/[-a-zA-Z0-9$]+(?:/[-a-zA-Z0-9]+)*
+# Google Maps
+\bmaps\.google\.com/maps\?[\w&;=]*
+# Google themes
+themes\.googleusercontent\.com/static/fonts/[^/\s"]+/v\d+/[^.]+.
+# Google CDN
+\bclients2\.google(?:usercontent|)\.com[-0-9a-zA-Z/.]*
+# Goo.gl
+/goo\.gl/[a-zA-Z0-9]+
+# Google Chrome Store
+\bchrome\.google\.com/webstore/detail/[-\w]*(?:/\w*|)
+# Google Books
+\bgoogle\.(?:\w{2,4})/books(?:/\w+)*\?[-\w\d=&#.]*
+# Google Fonts
+\bfonts\.(?:googleapis|gstatic)\.com/[-/?=:;+&0-9a-zA-Z]*
+# Google Forms
+\bforms\.gle/\w+
+# Google Scholar
+\bscholar\.google\.com/citations\?user=[A-Za-z0-9_]+
+# Google Colab Research Drive
+\bcolab\.research\.google\.com/drive/[-0-9a-zA-Z_?=]*
+
+# GitHub SHAs (api)
+\bapi.github\.com/repos(?:/[^/\s"]+){3}/[0-9a-f]+\b
+# GitHub SHAs (markdown)
+(?:\[`?[0-9a-f]+`?\]\(https:/|)/(?:www\.|)github\.com(?:/[^/\s"]+){2,}(?:/[^/\s")]+)(?:[0-9a-f]+(?:[-0-9a-zA-Z/#.]*|)\b|)
+# GitHub SHAs
+\bgithub\.com(?:/[^/\s"]+){2}[@#][0-9a-f]+\b
+# GitHub wiki
+\bgithub\.com/(?:[^/]+/){2}wiki/(?:(?:[^/]+/|)_history|[^/]+(?:/_compare|)/[0-9a-f.]{40,})\b
+# githubusercontent
+/[-a-z0-9]+\.githubusercontent\.com/[-a-zA-Z0-9?&=_\/.]*
+# githubassets
+\bgithubassets.com/[0-9a-f]+(?:[-/\w.]+)
+# gist github
+\bgist\.github\.com/[^/\s"]+/[0-9a-f]+
+# git.io
+\bgit\.io/[0-9a-zA-Z]+
+# GitHub JSON
+"node_id": "[-a-zA-Z=;:/0-9+]*"
+# Contributor
+\[[^\]]+\]\(https://github\.com/[^/\s"]+\)
+# GHSA
+GHSA(?:-[0-9a-z]{4}){3}
+
+# GitLab commit
+\bgitlab\.[^/\s"]*/\S+/\S+/commit/[0-9a-f]{7,16}#[0-9a-f]{40}\b
+# GitLab merge requests
+\bgitlab\.[^/\s"]*/\S+/\S+/-/merge_requests/\d+/diffs#[0-9a-f]{40}\b
+# GitLab uploads
+\bgitlab\.[^/\s"]*/uploads/[-a-zA-Z=;:/0-9+]*
+# GitLab commits
+\bgitlab\.[^/\s"]*/(?:[^/\s"]+/){2}commits?/[0-9a-f]+\b
+
+# binanace
+accounts.binance.com/[a-z/]*oauth/authorize\?[-0-9a-zA-Z&%]*
+
+# bitbucket diff
+\bapi\.bitbucket\.org/\d+\.\d+/repositories/(?:[^/\s"]+/){2}diff(?:stat|)(?:/[^/\s"]+){2}:[0-9a-f]+
+# bitbucket repositories commits
+\bapi\.bitbucket\.org/\d+\.\d+/repositories/(?:[^/\s"]+/){2}commits?/[0-9a-f]+
+# bitbucket commits
+\bbitbucket\.org/(?:[^/\s"]+/){2}commits?/[0-9a-f]+
+
+# bit.ly
+\bbit\.ly/\w+
+
+# bitrise
+\bapp\.bitrise\.io/app/[0-9a-f]*/[\w.?=&]*
+
+# bootstrapcdn.com
+\bbootstrapcdn\.com/[-./\w]+
+
+# cdn.cloudflare.com
+\bcdnjs\.cloudflare\.com/[./\w]+
+
+# circleci
+\bcircleci\.com/gh(?:/[^/\s"]+){1,5}.[a-z]+\?[-0-9a-zA-Z=&]+
+
+# gitter
+\bgitter\.im(?:/[^/\s"]+){2}\?at=[0-9a-f]+
+
+# gravatar
+\bgravatar\.com/avatar/[0-9a-f]+
+
+# ibm
+[a-z.]*ibm\.com/[-_#=:%!?~.\\/\d\w]*
+
+# imgur
+\bimgur\.com/[^.]+
+
+# Internet Archive
+\barchive\.org/web/\d+/(?:[-\w.?,'/\\+&%$#_:]*)
+
+# discord
+/discord(?:app\.com|\.gg)/(?:invite/)?[a-zA-Z0-9]{7,}
+
+# Disqus
+\bdisqus\.com/[-\w/%.()!?&=_]*
+
+# medium link
+\blink\.medium\.com/[a-zA-Z0-9]+
+# medium
+\bmedium\.com/\@?[^/\s"]+/[-\w]+
+
+# microsoft
+\b(?:https?://|)(?:(?:download\.visualstudio|docs|msdn2?|research)\.microsoft|blogs\.msdn)\.com/[-_a-zA-Z0-9()=./%]*
+# powerbi
+\bapp\.powerbi\.com/reportEmbed/[^"' ]*
+# vs devops
+\bvisualstudio.com(?::443|)/[-\w/?=%&.]*
+# microsoft store
+\bmicrosoft\.com/store/apps/\w+
+
+# mvnrepository.com
+\bmvnrepository\.com/[-0-9a-z./]+
+
+# now.sh
+/[0-9a-z-.]+\.now\.sh\b
+
+# oracle
+\bdocs\.oracle\.com/[-0-9a-zA-Z./_?#&=]*
+
+# chromatic.com
+/\S+.chromatic.com\S*[")]
+
+# codacy
+\bapi\.codacy\.com/project/badge/Grade/[0-9a-f]+
+
+# compai
+\bcompai\.pub/v1/png/[0-9a-f]+
+
+# mailgun api
+\.api\.mailgun\.net/v3/domains/[0-9a-z]+\.mailgun.org/messages/[0-9a-zA-Z=@]*
+# mailgun
+\b[0-9a-z]+.mailgun.org
+
+# /message-id/
+/message-id/[-\w@./%]+
+
+# Reddit
+\breddit\.com/r/[/\w_]*
+
+# requestb.in
+\brequestb\.in/[0-9a-z]+
+
+# sched
+\b[a-z0-9]+\.sched\.com\b
+
+# Slack url
+slack://[a-zA-Z0-9?&=]+
+# Slack
+\bslack\.com/[-0-9a-zA-Z/_~?&=.]*
+# Slack edge
+\bslack-edge\.com/[-a-zA-Z0-9?&=%./]+
+# Slack images
+\bslack-imgs\.com/[-a-zA-Z0-9?&=%.]+
+
+# shields.io
+\bshields\.io/[-\w/%?=&.:+;,]*
+
+# stackexchange -- https://stackexchange.com/feeds/sites
+\b(?:askubuntu|serverfault|stack(?:exchange|overflow)|superuser).com/(?:questions/\w+/[-\w]+|a/)
+
+# Sentry
+[0-9a-f]{32}\@o\d+\.ingest\.sentry\.io\b
+
+# Twitter markdown
+\[\@[^[/\]:]*?\]\(https://twitter.com/[^/\s"')]*(?:/status/\d+(?:\?[-_0-9a-zA-Z&=]*|)|)\)
+# Twitter hashtag
+\btwitter\.com/hashtag/[\w?_=&]*
+# Twitter status
+\btwitter\.com/[^/\s"')]*(?:/status/\d+(?:\?[-_0-9a-zA-Z&=]*|)|)
+# Twitter profile images
+\btwimg\.com/profile_images/[_\w./]*
+# Twitter media
+\btwimg\.com/media/[-_\w./?=]*
+# Twitter link shortened
+\bt\.co/\w+
+
+# facebook
+\bfburl\.com/[0-9a-z_]+
+# facebook CDN
+\bfbcdn\.net/[\w/.,]*
+# facebook watch
+\bfb\.watch/[0-9A-Za-z]+
+
+# dropbox
+\bdropbox\.com/sh?/[^/\s"]+/[-0-9A-Za-z_.%?=&;]+
+
+# ipfs protocol
+ipfs://[0-9a-z]*
+# ipfs url
+/ipfs/[0-9a-z]*
+
+# w3
+\bw3\.org/[-0-9a-zA-Z/#.]+
+
+# loom
+\bloom\.com/embed/[0-9a-f]+
+
+# regex101
+\bregex101\.com/r/[^/\s"]+/\d+
+
+# figma
+\bfigma\.com/file(?:/[0-9a-zA-Z]+/)+
+
+# freecodecamp.org
+\bfreecodecamp\.org/[-\w/.]+
+
+# image.tmdb.org
+\bimage\.tmdb\.org/[/\w.]+
+
+# mermaid
+\bmermaid\.ink/img/[-\w]+|\bmermaid-js\.github\.io/mermaid-live-editor/#/edit/[-\w]+
+
+# Wikipedia
+\ben\.wikipedia\.org/wiki/[-\w%.#]+
+
+# gitweb
+[^"\s]+/gitweb/\S+;h=[0-9a-f]+
+
+# HyperKitty lists
+/archives/list/[^@/]+\@[^/\s"]*/message/[^/\s"]*/
+
+# lists
+/thread\.html/[^"\s]+
+
+# list-management
+\blist-manage\.com/subscribe(?:[?&](?:u|id)=[0-9a-f]+)+
+
+# kubectl.kubernetes.io/last-applied-configuration
+"kubectl.kubernetes.io/last-applied-configuration": ".*"
+
+# pgp
+\bgnupg\.net/pks/lookup[?&=0-9a-zA-Z]*
+
+# Spotify
+\bopen\.spotify\.com/embed/playlist/\w+
+
+# Mastodon
+\bmastodon\.[-a-z.]*/(?:media/|\@)[?&=0-9a-zA-Z_]*
+
+# scastie
+\bscastie\.scala-lang\.org/[^/]+/\w+
+
+# images.unsplash.com
+\bimages\.unsplash\.com/(?:(?:flagged|reserve)/|)[-\w./%?=%&.;]+
+
+# pastebin
+\bpastebin\.com/[\w/]+
+
+# heroku
+\b\w+\.heroku\.com/source/archive/\w+
+
+# quip
+\b\w+\.quip\.com/\w+(?:(?:#|/issues/)\w+)?
+
+# badgen.net
+\bbadgen\.net/badge/[^")\]'\s]+
+
+# statuspage.io
+\w+\.statuspage\.io\b
+
+# media.giphy.com
+\bmedia\.giphy\.com/media/[^/]+/[\w.?&=]+
+
+# tinyurl
+\btinyurl\.com/\w+
+
+# getopts
+\bgetopts\s+(?:"[^"]+"|'[^']+')
+
+# ANSI color codes
+(?:\\(?:u00|x)1b|\x1b)\[\d+(?:;\d+|)m
+
+# URL escaped characters
+\%[0-9A-F][A-F]
+# IPv6
+\b(?:[0-9a-fA-F]{0,4}:){3,7}[0-9a-fA-F]{0,4}\b
+# c99 hex digits (not the full format, just one I've seen)
+0x[0-9a-fA-F](?:\.[0-9a-fA-F]*|)[pP]
+# Punycode
+\bxn--[-0-9a-z]+
+# sha
+sha\d+:[0-9]*[a-f]{3,}[0-9a-f]*
+# sha-... -- uses a fancy capture
+(['"]|&quot;)[0-9a-f]{40,}\g{-1}
+# hex runs
+\b[0-9a-fA-F]{16,}\b
+# hex in url queries
+=[0-9a-fA-F]*?(?:[A-F]{3,}|[a-f]{3,})[0-9a-fA-F]*?&
+# ssh
+(?:ssh-\S+|-nistp256) [-a-zA-Z=;:/0-9+]{12,}
+
+# PGP
+\b(?:[0-9A-F]{4} ){9}[0-9A-F]{4}\b
+# GPG keys
+\b(?:[0-9A-F]{4} ){5}(?: [0-9A-F]{4}){5}\b
+# Well known gpg keys
+.well-known/openpgpkey/[\w./]+
+
+# uuid:
+\b[0-9a-fA-F]{8}-(?:[0-9a-fA-F]{4}-){3}[0-9a-fA-F]{12}\b
+# hex digits including css/html color classes:
+(?:[\\0][xX]|\\u|[uU]\+|#x?|\%23)[0-9_a-fA-FgGrR]*?[a-fA-FgGrR]{2,}[0-9_a-fA-FgGrR]*(?:[uUlL]{0,3}|u\d+)\b
+# integrity
+integrity="sha\d+-[-a-zA-Z=;:/0-9+]{40,}"
+
+# https://www.gnu.org/software/groff/manual/groff.html
+# man troff content
+\\f[BCIPR]
+# '
+\\\(aq
+
+# .desktop mime types
+^MimeTypes?=.*$
+# .desktop localized entries
+^[A-Z][a-z]+\[[a-z]+\]=.*$
+# Localized .desktop content
+Name\[[^\]]+\]=.*
+
+# IServiceProvider
+\bI(?=(?:[A-Z][a-z]{2,})+\b)
+
+# crypt
+"\$2[ayb]\$.{56}"
+
+# scrypt / argon
+\$(?:scrypt|argon\d+[di]*)\$\S+
+
+# Input to GitHub JSON
+content: "[-a-zA-Z=;:/0-9+]*="
+
+# Python stringprefix / binaryprefix
+# Note that there's a high false positive rate, remove the `?=` and search for the regex to see if the matches seem like reasonable strings
+(?<!')\b(?:B|BR|Br|F|FR|Fr|R|RB|RF|Rb|Rf|U|UR|Ur|b|bR|br|f|fR|fr|r|rB|rF|rb|rf|u|uR|ur)'(?:[A-Z]{3,}|[A-Z][a-z]{2,}|[a-z]{3,})
+
+# Regular expressions for (P|p)assword
+\([A-Z]\|[a-z]\)[a-z]+
+
+# JavaScript regular expressions
+# javascript test regex
+/.*/[gim]*\.test\(
+# javascript match regex
+\.match\(/[^/\s"]*/[gim]*\s*
+# javascript match regex
+\.match\(/\\[b].*?/[gim]*\s*\)(?:;|$)
+# javascript regex
+^\s*/\\[b].*/[gim]*\s*(?:\)(?:;|$)|,$)
+# javascript replace regex
+\.replace\(/[^/\s"]*/[gim]*\s*,
+
+# Go regular expressions
+regexp?\.MustCompile\(`[^`]*`\)
+
+# sed regular expressions
+sed 's/(?:[^/]*?[a-zA-Z]{3,}[^/]*?/){2}
+
+# go install
+go install(?:\s+[a-z]+\.[-@\w/.]+)+
+
+# kubernetes pod status lists
+# https://kubernetes.io/docs/concepts/workloads/pods/pod-lifecycle/#pod-phase
+\w+(?:-\w+)+\s+\d+/\d+\s+(?:Running|Pending|Succeeded|Failed|Unknown)\s+
+
+# kubectl - pods in CrashLoopBackOff
+\w+-[0-9a-f]+-\w+\s+\d+/\d+\s+CrashLoopBackOff\s+
+
+# kubernetes object suffix
+-[0-9a-f]{10}-\w{5}\s
+
+# posthog secrets
+posthog\.init\((['"])phc_[^"',]+\g{-1},
+
+# xcode
+
+# xcodeproject scenes
+(?:Controller|ID|id)="\w{3}-\w{2}-\w{3}"
+
+# xcode api botches
+customObjectInstantitationMethod
+
+# font awesome classes
+\.fa-[-a-z0-9]+
+
+# Update Lorem based on your content (requires `ge` and `w` from https://github.com/jsoref/spelling; and `review` from https://github.com/check-spelling/check-spelling/wiki/Looking-for-items-locally )
+# grep '^[^#].*lorem' .github/actions/spelling/patterns.txt|perl -pne 's/.*i..\?://;s/\).*//' |tr '|' "\n"|sort -f |xargs -n1 ge|perl -pne 's/^[^:]*://'|sort -u|w|sed -e 's/ .*//'|w|review -
+# Warning, while `(?i)` is very neat and fancy, if you have some binary files that aren't proper unicode, you might run into:
+## Operation "substitution (s///)" returns its argument for non-Unicode code point 0x1C19AE (the code point will vary).
+## You could manually change `(?i)X...` to use `[Xx]...`
+## or you could add the files to your `excludes` file (a version after 0.0.19 should identify the file path)
+# Lorem
+(?:\w|\s|[,.])*\b(?i)(?:amet|consectetur|cursus|dolor|eros|ipsum|lacus|libero|ligula|lorem|magna|neque|nulla|suscipit|tempus)\b(?:\w|\s|[,.])*
+
+# Non-English
+[a-zA-Z]*[ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝßàáâãäåæçèéêëìíîïðñòóôõöøùúûüýÿĀāŁłŃńŅņŒœŚśŠšŜŝŸŽžź][a-zA-Z]{3}[a-zA-ZÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝßàáâãäåæçèéêëìíîïðñòóôõöøùúûüýÿĀāŁłŃńŅņŒœŚśŠšŜŝŸŽžź]*
+
+# French
+# This corpus only had capital letters, but you probably want lowercase ones as well.
+\b[LN]'+[a-z]{2,}\b
+
+# latex
+\\(?:n(?:ew|ormal|osub)|r(?:enew)|t(?:able(?:of|)|he|itle))(?=[a-z]+)
+
+# the negative lookahead here is to allow catching 'templatesz' as a misspelling
+# but to otherwise recognize a Windows path with \templates\foo.template or similar:
+\\(?:necessary|r(?:eport|esolve[dr]?|esult)|t(?:arget|emplates?))(?![a-z])
+# ignore long runs of a single character:
+\b([A-Za-z])\g{-1}{3,}\b
+# Note that the next example is no longer necessary if you are using
+# to match a string starting with a `#`, use a character-class:
+[#]backwards
+# version suffix <word>v#
+(?:(?<=[A-Z]{2})V|(?<=[a-z]{2}|[A-Z]{2})v)\d+(?:\b|(?=[a-zA-Z_]))
+# Compiler flags (Scala)
+(?:^|[\t ,>"'`=(])-J-[DPWXY](?=[A-Z]{2,}|[A-Z][a-z]|[a-z]{2,})
+# Compiler flags
+#(?:^|[\t ,"'`=(])-[DPWXYLlf](?=[A-Z]{2,}|[A-Z][a-z]|[a-z]{2,})
+
+# Compiler flags (linker)
+,-B
+# curl arguments
+\b(?:\\n|)curl(?:\s+-[a-zA-Z]{1,2}\b)*(?:\s+-[a-zA-Z]{3,})(?:\s+-[a-zA-Z]+)*
+# set arguments
+\bset(?:\s+-[abefimouxE]{1,2})*\s+-[abefimouxE]{3,}(?:\s+-[abefimouxE]+)*
+# tar arguments
+\b(?:\\n|)g?tar(?:\.exe|)(?:(?:\s+--[-a-zA-Z]+|\s+-[a-zA-Z]+|\s[ABGJMOPRSUWZacdfh-pr-xz]+\b)(?:=[^ ]*|))+
+# tput arguments -- https://man7.org/linux/man-pages/man5/terminfo.5.html -- technically they can be more than 5 chars long...
+\btput\s+(?:(?:-[SV]|-T\s*\w+)\s+)*\w{3,5}\b
+# macOS temp folders
+/var/folders/\w\w/[+\w]+/(?:T|-Caches-)/

.github/actions/spelling/excludes.txt

@@ -1,28 +1,39 @@
+# See https://github.com/check-spelling/check-spelling/wiki/Configuration-Examples:-excludes
 (?:(?i)\.png$)
+(?:^|/)(?i)COPYRIGHT
+(?:^|/)(?i)LICEN[CS]E
+(?:^|/)3rdparty/
 (?:^|/)dirs$
 (?:^|/)go\.mod$
 (?:^|/)go\.sum$
-(?:^|/)package-lock\.json$
+(?:^|/)package(?:-lock|)\.json$
 (?:^|/)sources(?:|\.dep)$
-SUMS$
+(?:^|/)vendor/
+\.a$
 \.ai$
+\.avi$
 \.bmp$
+\.bz2$
 \.cer$
 \.class$
 \.crl$
 \.crt$
 \.csr$
 \.dll$
+\.docx?$
+\.drawio$
 \.DS_Store$
 \.eot$
 \.eps$
 \.exe$
 \.gif$
+\.gitattributes$
 \.graffle$
 \.gz$
 \.icns$
 \.ico$
 \.jar$
+\.jks$
 \.jpeg$
 \.jpg$
 \.key$
@@ -30,28 +41,52 @@ SUMS$
 \.lock$
 \.map$
 \.min\..
+\.mod$
 \.mp3$
 \.mp4$
+\.o$
+\.ocf$
 \.otf$
 \.pbxproj$
 \.pdf$
 \.pem$
+\.png$
 \.psd$
+\.pyc$
 \.runsettings$
+\.s$
 \.sig$
 \.so$
 \.svg$
 \.svgz$
+\.svgz?$
 \.tar$
 \.tgz$
+\.tiff?$
 \.ttf$
 \.vsdx$
+\.wav$
+\.webm$
+\.webp$
 \.woff
+\.woff2?$
 \.xcf$
 \.xls
+\.xlsx?$
 \.xpm$
 \.yml$
 \.zip$
+^\.github/actions/spelling/
+^\.github/fabricbot.json$
+^\.gitignore$
+^\Q.git-blame-ignore-revs\E$
+^\Q.github/workflows/spelling.yml\E$
+^\Qdoc/reference/windows-terminal-logo.ans\E$
+^\Qsamples/ConPTY/EchoCon/EchoCon/EchoCon.vcxproj.filters\E$
+^\Qsrc/host/exe/Host.EXE.vcxproj.filters\E$
+^\Qsrc/host/ft_host/chafa.txt\E$
+^\Qsrc/tools/closetest/CloseTest.vcxproj.filters\E$
+^\XamlStyler.json$
 ^build/config/
 ^consolegit2gitfilters\.json$
 ^dep/
@@ -78,6 +113,5 @@ SUMS$
 ^src/tools/U8U16Test/(?:fr|ru|zh)\.txt$
 ^src/types/ut_types/UtilsTests.cpp$
 ^tools/ReleaseEngineering/ServicingPipeline.ps1$
-^\.github/actions/spelling/
-^\.gitignore$
-^\XamlStyler.json$
+ignore$
+SUMS$

.github/actions/spelling/expect/alphabet.txt

@@ -5,26 +5,19 @@ AAAAAABBBBBBCCC
 AAAAABBBBBBCCC
 abcd
 abcd
-abcde
-abcdef
-ABCDEFG
-ABCDEFGH
 ABCDEFGHIJ
 abcdefghijk
 ABCDEFGHIJKLMNO
 abcdefghijklmnop
 ABCDEFGHIJKLMNOPQRST
-abcdefghijklmnopqrstuvwxyz
 ABCG
 ABE
 abf
 BBBBB
 BBBBBBBB
-BBBBBBBBBBBBBBDDDD
 BBBBBCCC
 BBBBCCCCC
 BBGGRR
-CCE
 EFG
 EFGh
 QQQQQQQQQQABCDEFGHIJ
@@ -33,7 +26,6 @@ QQQQQQQQQQABCDEFGHIJKLMNOPQRSTQQQQQQQQQQ
 QQQQQQQQQQABCDEFGHIJPQRSTQQQQQQQQQQ
 qrstuvwxyz
 qwerty
-QWERTYUIOP
 qwertyuiopasdfg
 YYYYYYYDDDDDDDDDDD
 ZAAZZ

.github/actions/spelling/expect/web.txt

@@ -1,29 +1,6 @@
-http
-www
-easyrgb
-php
-ecma
-rapidtables
 WCAG
-freedesktop
-ycombinator
-robertelder
-kovidgoyal
-leonerd
-fixterms
 winui
 appshellintegration
 mdtauk
-cppreference
 gfycat
 Guake
-azurewebsites
-askubuntu
-dostips
-viewtopic
-rosettacode
-Rexx
-tldp
-HOWTO
-uwspace
-uwaterloo

.github/actions/spelling/line_forbidden.patterns

@@ -0,0 +1,62 @@
+# reject `m_data` as there's a certain OS which has evil defines that break things if it's used elsewhere
+# \bm_data\b
+
+# If you have a framework that uses `it()` for testing and `fit()` for debugging a specific test,
+# you might not want to check in code where you were debugging w/ `fit()`, in which case, you might want
+# to use this:
+#\bfit\(
+
+# s.b. GitHub
+\bGithub\b
+
+# s.b. GitLab
+\bGitlab\b
+
+# s.b. JavaScript
+\bJavascript\b
+
+# s.b. Microsoft
+\bMicroSoft\b
+
+# s.b. another
+\ban[- ]other\b
+
+# s.b. greater than
+\bgreater then\b
+
+# s.b. into
+#\sin to\s
+
+# s.b. opt-in
+\sopt in\s
+
+# s.b. less than
+\bless then\b
+
+# s.b. otherwise
+\bother[- ]wise\b
+
+# s.b. nonexistent
+\bnon existing\b
+\b[Nn]o[nt][- ]existent\b
+
+# s.b. preexisting
+[Pp]re[- ]existing
+
+# s.b. preempt
+[Pp]re[- ]empt\b
+
+# s.b. preemptively
+[Pp]re[- ]emptively
+
+# s.b. reentrancy
+[Rr]e[- ]entrancy
+
+# s.b. reentrant
+[Rr]e[- ]entrant
+
+# s.b. workaround(s)
+#\bwork[- ]arounds?\b
+
+# Reject duplicate words
+\s([A-Z]{3,}|[A-Z][a-z]{2,}|[a-z]{3,})\s\g{-1}\s

.github/actions/spelling/patterns/patterns.txt

@@ -1,11 +1,6 @@
-https://(?:(?:[-a-zA-Z0-9?&=]*\.|)microsoft\.com)/[-a-zA-Z0-9?&=_#\/.]*
-https://aka\.ms/[-a-zA-Z0-9?&=\/_]*
-https://www\.itscj\.ipsj\.or\.jp/iso-ir/[-0-9]+\.pdf
-https://www\.vt100\.net/docs/[-a-zA-Z0-9#_\/.]*
-https://www.w3.org/[-a-zA-Z0-9?&=\/_#]*
-https://(?:(?:www\.|)youtube\.com|youtu.be)/[-a-zA-Z0-9?&=]*
-https://(?:[a-z-]+\.|)github(?:usercontent|)\.com/[-a-zA-Z0-9?%&=_\/.+]*
-https://www.xfree86.org/[-a-zA-Z0-9?&=\/_#]*
+# See https://github.com/check-spelling/check-spelling/wiki/Configuration-Examples:-patterns
+
+https?://\S+
 [Pp]ublicKeyToken="?[0-9a-fA-F]{16}"?
 (?:[{"]|UniqueIdentifier>)[0-9a-fA-F]{8}-(?:[0-9a-fA-F]{4}-){3}[0-9a-fA-F]{12}(?:[}"]|</UniqueIdentifier)
 (?:0[Xx]|\\x|U\+|#)[a-f0-9A-FGgRr]{2,}[Uu]?[Ll]{0,2}\b
@@ -28,3 +23,74 @@ vcvars\w*
 ROY\sG\.\sBIV
 !(?:(?i)ESC)!\[
 !(?:(?i)CSI)!(?:\d+(?:;\d+|)m|[ABCDF])
+
+# Python stringprefix / binaryprefix
+\b(?:B|BR|Br|F|FR|Fr|R|RB|RF|Rb|Rf|U|UR|Ur|b|bR|br|f|fR|fr|r|rB|rF|rb|rf|u|uR|ur)'
+
+# Automatically suggested patterns
+# hit-count: 3831 file-count: 582
+# IServiceProvider
+\bI(?=(?:[A-Z][a-z]{2,})+\b)
+
+# hit-count: 71 file-count: 35
+# Compiler flags
+(?:^|[\t ,"'`=(])-[D](?=[A-Z]{2,}|[A-Z][a-z])
+(?:^|[\t ,"'`=(])-[X](?=[A-Z]{2,}|[A-Z][a-z]|[a-z]{2,})
+
+# hit-count: 41 file-count: 28
+# version suffix <word>v#
+(?:(?<=[A-Z]{2})V|(?<=[a-z]{2}|[A-Z]{2})v)\d+(?:\b|(?=[a-zA-Z_]))
+
+# hit-count: 20 file-count: 9
+# hex runs
+\b[0-9a-fA-F]{16,}\b
+
+# hit-count: 10 file-count: 7
+# uuid:
+\b[0-9a-fA-F]{8}-(?:[0-9a-fA-F]{4}-){3}[0-9a-fA-F]{12}\b
+
+# hit-count: 4 file-count: 4
+# mailto urls
+mailto:[-a-zA-Z=;:/?%&0-9+@.]{3,}
+
+# hit-count: 4 file-count: 1
+# ANSI color codes
+(?:\\(?:u00|x)1b|\x1b)\[\d+(?:;\d+|)m
+
+# hit-count: 2 file-count: 1
+# latex
+\\(?:n(?:ew|ormal|osub)|r(?:enew)|t(?:able(?:of|)|he|itle))(?=[a-z]+)
+
+# hit-count: 1 file-count: 1
+# hex digits including css/html color classes:
+(?:[\\0][xX]|\\u|[uU]\+|#x?|\%23)[0-9_a-fA-FgGrR]*?[a-fA-FgGrR]{2,}[0-9_a-fA-FgGrR]*(?:[uUlL]{0,3}|u\d+)\b
+
+# hit-count: 1 file-count: 1
+# Non-English
+[a-zA-Z]*[ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝßàáâãäåæçèéêëìíîïðñòóôõöøùúûüýÿĀāŁłŃńŅņŒœŚśŠšŜŝŸŽžź][a-zA-Z]{3}[a-zA-ZÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝßàáâãäåæçèéêëìíîïðñòóôõöøùúûüýÿĀāŁłŃńŅņŒœŚśŠšŜŝŸŽžź]*
+
+# hit-count: 1 file-count: 1
+# French
+# This corpus only had capital letters, but you probably want lowercase ones as well.
+\b[LN]'+[a-z]{2,}\b
+
+# acceptable duplicates
+# ls directory listings
+[-bcdlpsw](?:[-r][-w][-sx]){3}\s+\d+\s+(\S+)\s+\g{-1}\s+\d+\s+
+# C/idl types + English ...
+\s(Guid|long|LONG|that) \g{-1}\s
+
+# javadoc / .net
+(?:[\\@](?:groupname|param)|(?:public|private)(?:\s+static|\s+readonly)*)\s+(\w+)\s+\g{-1}\s
+
+# Commit message -- Signed-off-by and friends
+^\s*(?:(?:Based-on-patch|Co-authored|Helped|Mentored|Reported|Reviewed|Signed-off)-by|Thanks-to): (?:[^<]*<[^>]*>|[^<]*)\s*$
+
+# Autogenerated revert commit message
+^This reverts commit [0-9a-f]{40}\.$
+
+# vtmode
+--vtmode\s+(\w+)\s+\g{-1}\s
+
+# ignore long runs of a single character:
+\b([A-Za-z])\g{-1}{3,}\b

.github/actions/spelling/reject.txt

@@ -1,22 +1,12 @@
 ^attache$
 ^attacher$
 ^attachers$
-^spae$
-^spaebook$
-^spaecraft$
-^spaed$
-^spaedom$
-^spaeing$
-^spaeings$
-^spae-man$
-^spaeman$
-^spaer$
-^Spaerobee$
-^spaes$
-^spaewife$
-^spaewoman$
-^spaework$
-^spaewright$
-^wether$
-^wethers$
-^wetherteg$
+benefitting
+occurences?
+^dependan.*
+^oer$
+Sorce
+^[Ss]pae.*
+^untill$
+^untilling$
+^wether.*

.github/workflows/spelling2.yml

@@ -1,20 +1,134 @@
 # spelling.yml is blocked per https://github.com/check-spelling/check-spelling/security/advisories/GHSA-g86g-chm8-7r2p
 name: Spell checking
+
+# Comment management is handled through a secondary job, for details see:
+# https://github.com/check-spelling/check-spelling/wiki/Feature%3A-Restricted-Permissions
+#
+# `jobs.comment-push` runs when a push is made to a repository and the `jobs.spelling` job needs to make a comment
+#   (in odd cases, it might actually run just to collapse a commment, but that's fairly rare)
+#   it needs `contents: write` in order to add a comment.
+#
+# `jobs.comment-pr` runs when a pull_request is made to a repository and the `jobs.spelling` job needs to make a comment
+#   or collapse a comment (in the case where it had previously made a comment and now no longer needs to show a comment)
+#   it needs `pull-requests: write` in order to manipulate those comments.
+
+# Updating pull request branches is managed via comment handling.
+# For details, see: https://github.com/check-spelling/check-spelling/wiki/Feature:-Update-expect-list
+#
+# These elements work together to make it happen:
+#
+# `on.issue_comment`
+#   This event listens to comments by users asking to update the metadata.
+#
+# `jobs.update`
+#   This job runs in response to an issue_comment and will push a new commit
+#   to update the spelling metadata.
+#
+# `with.experimental_apply_changes_via_bot`
+#   Tells the action to support and generate messages that enable it
+#   to make a commit to update the spelling metadata.
+#
+# `with.ssh_key`
+#   In order to trigger workflows when the commit is made, you can provide a
+#   secret (typically, a write-enabled github deploy key).
+#
+#   For background, see: https://github.com/check-spelling/check-spelling/wiki/Feature:-Update-with-deploy-key
+
 on:
-  pull_request_target:
   push:
+    branches:
+    - "**"
+    tags-ignore:
+    - "**"
+  pull_request_target:
+    branches:
+    - "**"
+    tags-ignore:
+    - "**"
+    types:
+    - 'opened'
+    - 'reopened'
+    - 'synchronize'
+  issue_comment:
+    types:
+    - 'created'
 
 jobs:
   spelling:
     name: Spell checking
+    permissions:
+      contents: read
+      pull-requests: read
+      actions: read
+    outputs:
+      followup: ${{ steps.spelling.outputs.followup }}
     runs-on: ubuntu-latest
+    if: "contains(github.event_name, 'pull_request') || github.event_name == 'push'"
+    concurrency:
+      group: spelling-${{ github.event.pull_request.number || github.ref }}
+      # note: If you use only_check_changed_files, you do not want cancel-in-progress
+      cancel-in-progress: true
     steps:
-    - name: checkout-merge
-      if: "contains(github.event_name, 'pull_request')"
-      uses: actions/checkout@v2
+    - name: check-spelling
+      id: spelling
+      uses: check-spelling/check-spelling@v0.0.21
       with:
-        ref: refs/pull/${{github.event.pull_request.number}}/merge
-    - name: checkout
-      if: "!contains(github.event_name, 'pull_request')"
-      uses: actions/checkout@v2
-    - uses: check-spelling/check-spelling@v0.0.19
+        suppress_push_for_open_pull_request: 1
+        checkout: true
+        check_file_names: 1
+        spell_check_this: check-spelling/spell-check-this@prerelease
+        post_comment: 0
+        use_magic_file: 1
+        extra_dictionary_limit: 10
+        extra_dictionaries:
+          cspell:software-terms/src/software-terms.txt
+          cspell:python/src/python/python-lib.txt
+          cspell:node/node.txt
+          cspell:cpp/src/stdlib-c.txt
+          cspell:cpp/src/stdlib-cpp.txt
+          cspell:fullstack/fullstack.txt
+          cspell:filetypes/filetypes.txt
+          cspell:html/html.txt
+          cspell:cpp/src/compiler-msvc.txt
+          cspell:python/src/common/extra.txt
+          cspell:powershell/powershell.txt
+          cspell:aws/aws.txt
+          cspell:cpp/src/lang-keywords.txt
+          cspell:npm/npm.txt
+          cspell:dotnet/dotnet.txt
+          cspell:python/src/python/python.txt
+          cspell:css/css.txt
+          cspell:cpp/src/stdlib-cmath.txt
+        check_extra_dictionaries: ''
+
+  comment-push:
+    name: Report (Push)
+    # If your workflow isn't running on push, you can remove this job
+    runs-on: ubuntu-latest
+    needs: spelling
+    permissions:
+      contents: write
+    if: (success() || failure()) && needs.spelling.outputs.followup && github.event_name == 'push'
+    steps:
+    - name: comment
+      uses: check-spelling/check-spelling@v0.0.21
+      with:
+        checkout: true
+        spell_check_this: check-spelling/spell-check-this@prerelease
+        task: ${{ needs.spelling.outputs.followup }}
+
+  comment-pr:
+    name: Report (PR)
+    # If you workflow isn't running on pull_request*, you can remove this job
+    runs-on: ubuntu-latest
+    needs: spelling
+    permissions:
+      pull-requests: write
+    if: (success() || failure()) && needs.spelling.outputs.followup && contains(github.event_name, 'pull_request')
+    steps:
+    - name: comment
+      uses: check-spelling/check-spelling@v0.0.21
+      with:
+        checkout: true
+        spell_check_this: check-spelling/spell-check-this@prerelease
+        task: ${{ needs.spelling.outputs.followup }}

src/cascadia/TerminalApp/AppLogic.cpp

@@ -367,11 +367,12 @@ namespace winrt::TerminalApp::implementation
         // details here, but it does have the desired effect.
         // It's not enough to set the theme on the dialog alone.
         auto themingLambda{ [this](const Windows::Foundation::IInspectable& sender, const RoutedEventArgs&) {
-            auto theme{ _settings.GlobalSettings().Theme() };
+            auto theme{ _settings.GlobalSettings().CurrentTheme() };
+            auto requestedTheme{ theme.Window().RequestedTheme() };
             auto element{ sender.try_as<winrt::Windows::UI::Xaml::FrameworkElement>() };
             while (element)
             {
-                element.RequestedTheme(theme);
+                element.RequestedTheme(requestedTheme);
                 element = element.Parent().try_as<winrt::Windows::UI::Xaml::FrameworkElement>();
             }
         } };
@@ -743,7 +744,7 @@ namespace winrt::TerminalApp::implementation
             LoadSettings();
         }
 
-        return _settings.GlobalSettings().Theme();
+        return _settings.GlobalSettings().CurrentTheme().Window().RequestedTheme();
     }
 
     bool AppLogic::GetShowTabsInTitlebar()
@@ -964,7 +965,7 @@ namespace winrt::TerminalApp::implementation
 
     void AppLogic::_RefreshThemeRoutine()
     {
-        _ApplyTheme(_settings.GlobalSettings().Theme());
+        _ApplyTheme(_settings.GlobalSettings().CurrentTheme().Window().RequestedTheme());
     }
 
     // Function Description:
@@ -1219,6 +1220,19 @@ namespace winrt::TerminalApp::implementation
         return {};
     }
 
+    winrt::Windows::UI::Xaml::Media::Brush AppLogic::TitlebarBrush()
+    {
+        if (_root)
+        {
+            return _root->TitlebarBrush();
+        }
+        return { nullptr };
+    }
+    void AppLogic::WindowActivated(const bool activated)
+    {
+        _root->WindowActivated(activated);
+    }
+
     bool AppLogic::HasCommandlineArguments() const noexcept
     {
         return _hasCommandLineArguments;
@@ -1645,4 +1659,15 @@ namespace winrt::TerminalApp::implementation
     {
         return _settings.GlobalSettings().ShowTitleInTitlebar();
     }
+
+    Microsoft::Terminal::Settings::Model::Theme AppLogic::Theme()
+    {
+        if (!_loadedInitialSettings)
+        {
+            // Load settings if we haven't already
+            LoadSettings();
+        }
+        return _settings.GlobalSettings().CurrentTheme();
+    }
+
 }

src/cascadia/TerminalApp/AppLogic.h

@@ -117,6 +117,8 @@ namespace winrt::TerminalApp::implementation
         void WindowVisibilityChanged(const bool showOrHide);
 
         winrt::TerminalApp::TaskbarState TaskbarState();
+        winrt::Windows::UI::Xaml::Media::Brush TitlebarBrush();
+        void WindowActivated(const bool activated);
 
         bool GetMinimizeToNotificationArea();
         bool GetAlwaysShowNotificationIcon();
@@ -127,7 +129,13 @@ namespace winrt::TerminalApp::implementation
 
         Windows::Foundation::Collections::IMapView<Microsoft::Terminal::Control::KeyChord, Microsoft::Terminal::Settings::Model::Command> GlobalHotkeys();
 
+        Microsoft::Terminal::Settings::Model::Theme Theme();
+
         // -------------------------------- WinRT Events ---------------------------------
+        // PropertyChanged is surprisingly not a typed event, so we'll define that one manually.
+        winrt::event_token PropertyChanged(Windows::UI::Xaml::Data::PropertyChangedEventHandler const& handler) { return _root->PropertyChanged(handler); }
+        void PropertyChanged(winrt::event_token const& token) { _root->PropertyChanged(token); }
+
         TYPED_EVENT(RequestedThemeChanged, winrt::Windows::Foundation::IInspectable, winrt::Windows::UI::Xaml::ElementTheme);
         TYPED_EVENT(SettingsChanged, winrt::Windows::Foundation::IInspectable, winrt::Windows::Foundation::IInspectable);
         TYPED_EVENT(SystemMenuChangeRequested, winrt::Windows::Foundation::IInspectable, winrt::TerminalApp::SystemMenuChangeArgs);

src/cascadia/TerminalApp/AppLogic.idl

@@ -35,7 +35,7 @@ namespace TerminalApp
 
     // See IDialogPresenter and TerminalPage's DialogPresenter for more
     // information.
-    [default_interface] runtimeclass AppLogic : IDirectKeyListener, IDialogPresenter
+    [default_interface] runtimeclass AppLogic : IDirectKeyListener, IDialogPresenter, Windows.UI.Xaml.Data.INotifyPropertyChanged
     {
         AppLogic();
 
@@ -94,6 +94,8 @@ namespace TerminalApp
         void WindowVisibilityChanged(Boolean showOrHide);
 
         TaskbarState TaskbarState{ get; };
+        Windows.UI.Xaml.Media.Brush TitlebarBrush { get; };
+        void WindowActivated(Boolean activated);
 
         Boolean ShouldUsePersistedLayout();
         Boolean ShouldImmediatelyHandoffToElevated();
@@ -105,6 +107,8 @@ namespace TerminalApp
         Boolean GetAlwaysShowNotificationIcon();
         Boolean GetShowTitleInTitlebar();
 
+        Microsoft.Terminal.Settings.Model.Theme Theme { get; };
+
         FindTargetWindowResult FindTargetWindow(String[] args);
 
         Windows.Foundation.Collections.IMapView<Microsoft.Terminal.Control.KeyChord, Microsoft.Terminal.Settings.Model.Command> GlobalHotkeys();

src/cascadia/TerminalApp/HighlightedText.h

@@ -3,8 +3,6 @@
 
 #pragma once
 
-#include "winrt/Microsoft.UI.Xaml.Controls.h"
-
 #include "HighlightedTextSegment.g.h"
 #include "HighlightedText.g.h"
 

src/cascadia/TerminalApp/TabManagement.cpp

@@ -148,6 +148,8 @@ namespace winrt::TerminalApp::implementation
                 // Possibly update the icon of the tab.
                 page->_UpdateTabIcon(*tab);
 
+                page->_updateTabRowColors();
+
                 // Update the taskbar progress as well. We'll raise our own
                 // SetTaskbarProgress event here, to get tell the hosting
                 // application to re-query this value from us.
@@ -909,6 +911,8 @@ namespace winrt::TerminalApp::implementation
                 _TitleChangedHandlers(*this, tab.Title());
             }
 
+            _updateTabRowColors();
+
             auto tab_impl = _GetTerminalTabImpl(tab);
             if (tab_impl)
             {

src/cascadia/TerminalApp/TerminalPage.cpp

@@ -160,43 +160,6 @@ namespace winrt::TerminalApp::implementation
 
         const auto isElevated = IsElevated();
 
-        if (_settings.GlobalSettings().UseAcrylicInTabRow())
-        {
-            const auto res = Application::Current().Resources();
-            const auto lightKey = winrt::box_value(L"Light");
-            const auto darkKey = winrt::box_value(L"Dark");
-            const auto tabViewBackgroundKey = winrt::box_value(L"TabViewBackground");
-
-            for (const auto& dictionary : res.MergedDictionaries())
-            {
-                // Don't change MUX resources
-                if (dictionary.Source())
-                {
-                    continue;
-                }
-
-                for (const auto& kvPair : dictionary.ThemeDictionaries())
-                {
-                    const auto themeDictionary = kvPair.Value().as<winrt::Windows::UI::Xaml::ResourceDictionary>();
-
-                    if (themeDictionary.HasKey(tabViewBackgroundKey))
-                    {
-                        const auto backgroundSolidBrush = themeDictionary.Lookup(tabViewBackgroundKey).as<Media::SolidColorBrush>();
-
-                        const til::color backgroundColor = backgroundSolidBrush.Color();
-
-                        const auto acrylicBrush = Media::AcrylicBrush();
-                        acrylicBrush.BackgroundSource(Media::AcrylicBackgroundSource::HostBackdrop);
-                        acrylicBrush.FallbackColor(backgroundColor);
-                        acrylicBrush.TintColor(backgroundColor);
-                        acrylicBrush.TintOpacity(0.5);
-
-                        themeDictionary.Insert(tabViewBackgroundKey, acrylicBrush);
-                    }
-                }
-            }
-        }
-
         _tabRow.PointerMoved({ get_weak(), &TerminalPage::_RestorePointerCursorHandler });
         _tabView.CanReorderTabs(!isElevated);
         _tabView.CanDragTabs(!isElevated);
@@ -219,6 +182,7 @@ namespace winrt::TerminalApp::implementation
             // Inform the host that our titlebar content has changed.
             _SetTitleBarContentHandlers(*this, _tabRow);
         }
+        _updateTabRowColors();
 
         // Hookup our event handlers to the ShortcutActionDispatch
         _RegisterActionCallbacks();
@@ -1430,6 +1394,17 @@ namespace winrt::TerminalApp::implementation
 
         term.ConnectionStateChanged({ get_weak(), &TerminalPage::_ConnectionStateChangedHandler });
 
+        auto weakThis{ get_weak() };
+        term.PropertyChanged([weakThis](auto& /*sender*/, auto& e) {
+            if (auto page{ weakThis.get() })
+            {
+                if (e.PropertyName() == L"BackgroundBrush")
+                {
+                    page->_updateTabRowColors();
+                }
+            }
+        });
+
         term.ShowWindowChanged({ get_weak(), &TerminalPage::_ShowWindowChangedHandler });
     }
 
@@ -1469,37 +1444,9 @@ namespace winrt::TerminalApp::implementation
             }
         });
 
-        // react on color changed events
-        hostingTab.ColorSelected([weakTab, weakThis](auto&& color) {
-            auto page{ weakThis.get() };
-            auto tab{ weakTab.get() };
-
-            if (page && tab && (tab->FocusState() != FocusState::Unfocused))
-            {
-                page->_SetNonClientAreaColors(color);
-            }
-        });
-
-        hostingTab.ColorCleared([weakTab, weakThis]() {
-            auto page{ weakThis.get() };
-            auto tab{ weakTab.get() };
-
-            if (page && tab && (tab->FocusState() != FocusState::Unfocused))
-            {
-                page->_ClearNonClientAreaColors();
-            }
-        });
-
         // Add an event handler for when the terminal or tab wants to set a
         // progress indicator on the taskbar
         hostingTab.TaskbarProgressChanged({ get_weak(), &TerminalPage::_SetTaskbarProgressHandler });
-
-        // TODO GH#3327: Once we support colorizing the NewTab button based on
-        // the color of the tab, we'll want to make sure to call
-        // _ClearNewTabButtonColor here, to reset it to the default (for the
-        // newly created tab).
-        // remove any colors left by other colored tabs
-        // _ClearNewTabButtonColor();
     }
 
     // Method Description:
@@ -2697,6 +2644,13 @@ namespace winrt::TerminalApp::implementation
         WUX::Media::Animation::Timeline::AllowDependentAnimations(!_settings.GlobalSettings().DisableAnimations());
 
         _tabRow.ShowElevationShield(IsElevated() && _settings.GlobalSettings().ShowAdminShield());
+
+        Media::SolidColorBrush transparent{ Windows::UI::Colors::Transparent() };
+        _tabView.Background(transparent);
+
+        ////////////////////////////////////////////////////////////////////////
+        // Begin Theme handling
+        _updateTabRowColors();
     }
 
     // This is a helper to aid in sorting commands by their `Name`s, alphabetically.
@@ -3081,32 +3035,6 @@ namespace winrt::TerminalApp::implementation
         _newTabButton.Foreground(foregroundBrush);
     }
 
-    // Method Description:
-    // - Sets the tab split button color when a new tab color is selected
-    // - This method could also set the color of the title bar and tab row
-    // in the future
-    // Arguments:
-    // - selectedTabColor: The color of the newly selected tab
-    // Return Value:
-    // - <none>
-    void TerminalPage::_SetNonClientAreaColors(const Windows::UI::Color& /*selectedTabColor*/)
-    {
-        // TODO GH#3327: Look at what to do with the NC area when we have XAML theming
-    }
-
-    // Method Description:
-    // - Clears the tab split button color when the tab's color is cleared
-    // - This method could also clear the color of the title bar and tab row
-    // in the future
-    // Arguments:
-    // - <none>
-    // Return Value:
-    // - <none>
-    void TerminalPage::_ClearNonClientAreaColors()
-    {
-        // TODO GH#3327: Look at what to do with the NC area when we have XAML theming
-    }
-
     // Function Description:
     // - This is a helper method to get the commandline out of a
     //   ExecuteCommandline action, break it into subcommands, and attempt to
@@ -3507,10 +3435,11 @@ namespace winrt::TerminalApp::implementation
     // - <none>
     void TerminalPage::_UpdateTeachingTipTheme(winrt::Windows::UI::Xaml::FrameworkElement element)
     {
-        auto theme{ _settings.GlobalSettings().Theme() };
+        auto theme{ _settings.GlobalSettings().CurrentTheme() };
+        auto requestedTheme{ theme.Window().RequestedTheme() };
         while (element)
         {
-            element.RequestedTheme(theme);
+            element.RequestedTheme(requestedTheme);
             element = element.Parent().try_as<winrt::Windows::UI::Xaml::FrameworkElement>();
         }
     }
@@ -4014,4 +3943,121 @@ namespace winrt::TerminalApp::implementation
         applicationState.DismissedMessages(std::move(messages));
     }
 
+    void TerminalPage::_updateTabRowColors()
+    {
+        if (_settings == nullptr)
+        {
+            return;
+        }
+
+        const auto theme = _settings.GlobalSettings().CurrentTheme();
+        auto requestedTheme{ theme.Window().RequestedTheme() };
+
+        const auto res = Application::Current().Resources();
+
+        // XAML Hacks:
+        //
+        // the App is always in the OS theme, so the
+        // App::Current().Resources() lookup will always get the value for the
+        // OS theme, not the requested theme.
+        //
+        // This helper allows us to instead lookup the value of a resource
+        // specified by `key` for the given `requestedTheme`, from the
+        // dictionaries in App.xaml. Make sure the value is actually there!
+        // Otherwise this'll throw like any other Lookup for a resource that
+        // isn't there.
+        static const auto lookup = [](auto& res, auto& requestedTheme, auto& key) {
+            // You want the Default version of the resource? Great, the App is
+            // always in the OS theme. Just look it up and be done.
+            if (requestedTheme == ElementTheme::Default)
+            {
+                return res.Lookup(key);
+            }
+            static const auto lightKey = winrt::box_value(L"Light");
+            static const auto darkKey = winrt::box_value(L"Dark");
+            // There isn't an ElementTheme::HighContrast.
+
+            auto requestedThemeKey = requestedTheme == ElementTheme::Dark ? darkKey : lightKey;
+            for (const auto& dictionary : res.MergedDictionaries())
+            {
+                // Don't look in the MUX resources. They come first. A person
+                // with more patience than me may find a way to look through our
+                // dictionaries first, then the MUX ones, but that's not needed
+                // currently
+                if (dictionary.Source())
+                {
+                    continue;
+                }
+                // Look through the theme dictionaries we defined:
+                for (const auto& [dictionaryKey, dict] : dictionary.ThemeDictionaries())
+                {
+                    // Does the key for this dict match the theme we're looking for?
+                    if (winrt::unbox_value<winrt::hstring>(dictionaryKey) !=
+                        winrt::unbox_value<winrt::hstring>(requestedThemeKey))
+                    {
+                        // No? skip it.
+                        continue;
+                    }
+                    // Look for the requested resource in this dict.
+                    const auto themeDictionary = dict.as<winrt::Windows::UI::Xaml::ResourceDictionary>();
+                    if (themeDictionary.HasKey(key))
+                    {
+                        return themeDictionary.Lookup(key);
+                    }
+                }
+            }
+
+            // We didn't find it in the requested dict, fall back to the default dictionary.
+            return res.Lookup(key);
+        };
+
+        // Use our helper to lookup the theme-aware version of the resource.
+        const auto tabViewBackgroundKey = winrt::box_value(L"TabViewBackground");
+        const auto backgroundSolidBrush = lookup(res, requestedTheme, tabViewBackgroundKey).as<Media::SolidColorBrush>();
+
+        til::color bgColor = backgroundSolidBrush.Color();
+
+        if (_settings.GlobalSettings().UseAcrylicInTabRow())
+        {
+            const til::color backgroundColor = backgroundSolidBrush.Color();
+            const auto acrylicBrush = Media::AcrylicBrush();
+            acrylicBrush.BackgroundSource(Media::AcrylicBackgroundSource::HostBackdrop);
+            acrylicBrush.FallbackColor(backgroundColor);
+            acrylicBrush.TintColor(backgroundColor);
+            acrylicBrush.TintOpacity(0.5);
+
+            TitlebarBrush(acrylicBrush);
+            bgColor = backgroundColor;
+        }
+        else if (theme.TabRow() && theme.TabRow().Background())
+        {
+            const auto tabRowBg = theme.TabRow().Background();
+            const auto terminalBrush = [this]() -> Media::Brush { if(const auto& control{_GetActiveControl()}){ return control.BackgroundBrush(); } return nullptr; }();
+            const auto themeBrush{ tabRowBg.Evaluate(res, terminalBrush, true) };
+
+            bgColor = ThemeColor::ColorFromBrush(themeBrush);
+
+            TitlebarBrush(themeBrush);
+        }
+        else
+        {
+            // Nothing was set in the theme - fall back to our original `TabViewBackground` color.
+            TitlebarBrush(backgroundSolidBrush);
+        }
+
+        _tabRow.Background(TitlebarBrush());
+
+        // Update the new tab button to have better contrast with the new color.
+        // In theory, it would be convenient to also change these for the
+        // inactive tabs as well, but we're leaving that as a follow up.
+        _SetNewTabButtonColor(bgColor, bgColor);
+    }
+
+    void TerminalPage::WindowActivated(const bool activated)
+    {
+        // Stash if we're activated. Use that when we reload
+        // the settings, change active panes, etc.
+        _activated = activated;
+        _updateTabRowColors();
+    }
 }

src/cascadia/TerminalApp/TerminalPage.h

@@ -134,6 +134,7 @@ namespace winrt::TerminalApp::implementation
         bool IsElevated() const noexcept;
 
         void OpenSettingsUI();
+        void WindowActivated(const bool activated);
 
         WINRT_CALLBACK(PropertyChanged, Windows::UI::Xaml::Data::PropertyChangedEventHandler);
 
@@ -157,6 +158,8 @@ namespace winrt::TerminalApp::implementation
         TYPED_EVENT(QuitRequested, IInspectable, IInspectable);
         TYPED_EVENT(ShowWindowChanged, IInspectable, winrt::Microsoft::Terminal::Control::ShowWindowArgs)
 
+        WINRT_OBSERVABLE_PROPERTY(winrt::Windows::UI::Xaml::Media::Brush, TitlebarBrush, _PropertyChangedHandlers, nullptr);
+
     private:
         friend struct TerminalPageT<TerminalPage>; // for Xaml to bind events
         std::optional<HWND> _hostingHwnd;
@@ -196,6 +199,8 @@ namespace winrt::TerminalApp::implementation
         std::optional<int> _rearrangeFrom{};
         std::optional<int> _rearrangeTo{};
         bool _removing{ false };
+
+        bool _activated{ false };
         bool _visible{ true };
 
         std::vector<std::vector<Microsoft::Terminal::Settings::Model::ActionAndArgs>> _previouslyClosedPanesAndTabs{};
@@ -383,8 +388,6 @@ namespace winrt::TerminalApp::implementation
 
         void _RefreshUIForSettingsReload();
 
-        void _SetNonClientAreaColors(const Windows::UI::Color& selectedTabColor);
-        void _ClearNonClientAreaColors();
         void _SetNewTabButtonColor(const Windows::UI::Color& color, const Windows::UI::Color& accentColor);
         void _ClearNewTabButtonColor();
 
@@ -442,6 +445,8 @@ namespace winrt::TerminalApp::implementation
         static bool _IsMessageDismissed(const winrt::Microsoft::Terminal::Settings::Model::InfoBarMessage& message);
         static void _DismissMessage(const winrt::Microsoft::Terminal::Settings::Model::InfoBarMessage& message);
 
+        void _updateTabRowColors();
+
         winrt::fire_and_forget _ShowWindowChangedHandler(const IInspectable sender, const winrt::Microsoft::Terminal::Control::ShowWindowArgs args);
 
 #pragma region ActionHandlers

src/cascadia/TerminalApp/TerminalPage.idl

@@ -45,6 +45,9 @@ namespace TerminalApp
 
         TaskbarState TaskbarState{ get; };
 
+        Windows.UI.Xaml.Media.Brush TitlebarBrush { get; };
+        void WindowActivated(Boolean activated);
+
         event Windows.Foundation.TypedEventHandler<Object, String> TitleChanged;
         event Windows.Foundation.TypedEventHandler<Object, LastTabClosedEventArgs> LastTabClosed;
         event Windows.Foundation.TypedEventHandler<Object, Windows.UI.Xaml.UIElement> SetTitleBarContent;

src/cascadia/TerminalApp/TitlebarControl.cpp

@@ -17,17 +17,17 @@ namespace winrt::TerminalApp::implementation
     {
         InitializeComponent();
 
-        // Register our event handlers on the MMC buttons.
-        MinMaxCloseControl().MinimizeClick({ this, &TitlebarControl::Minimize_Click });
-        MinMaxCloseControl().MaximizeClick({ this, &TitlebarControl::Maximize_Click });
-        MinMaxCloseControl().CloseClick({ this, &TitlebarControl::Close_Click });
+        // // Register our event handlers on the MMC buttons.
+        // MinMaxCloseControl().MinimizeClick({ this, &TitlebarControl::Minimize_Click });
+        // MinMaxCloseControl().MaximizeClick({ this, &TitlebarControl::Maximize_Click });
+        // MinMaxCloseControl().CloseClick({ this, &TitlebarControl::Close_Click });
     }
 
     double TitlebarControl::CaptionButtonWidth()
     {
         // Divide by three, since we know there are only three buttons. When
         // Windows 12 comes along and adds another, we can update this /s
-        static auto width{ MinMaxCloseControl().ActualWidth() / 3.0 };
+        static auto width{ CaptionButtonSpace().ActualWidth() / 3.0 };
         return width;
     }
 
@@ -45,7 +45,7 @@ namespace winrt::TerminalApp::implementation
                                            const Windows::UI::Xaml::SizeChangedEventArgs& /*e*/)
     {
         const auto windowWidth = ActualWidth();
-        const auto minMaxCloseWidth = MinMaxCloseControl().ActualWidth();
+        const auto minMaxCloseWidth = CaptionButtonSpace().ActualWidth();
         const auto dragBarMinWidth = DragBar().MinWidth();
         const auto maxWidth = windowWidth - minMaxCloseWidth - dragBarMinWidth;
         // Only set our MaxWidth if it's greater than 0. Setting it to a
@@ -98,20 +98,62 @@ namespace winrt::TerminalApp::implementation
 
     void TitlebarControl::SetWindowVisualState(WindowVisualState visualState)
     {
-        MinMaxCloseControl().SetWindowVisualState(visualState);
+        // MinMaxCloseControl().SetWindowVisualState(visualState);
+
+        // Look up the heights we should use for the caption buttons from our
+        // XAML resources. "CaptionButtonHeightWindowed" and
+        // "CaptionButtonHeightMaximized" define the size we should use for the
+        // caption buttons height for the windowed and maximized states,
+        // respectively.
+        //
+        // use C++11 magic statics to make sure we only do this once.
+        static auto heights = [this]() {
+            const auto res = Resources();
+            const auto windowedHeightKey = winrt::box_value(L"CaptionButtonHeightWindowed");
+            const auto maximizedHeightKey = winrt::box_value(L"CaptionButtonHeightMaximized");
+
+            auto windowedHeight = 0.0;
+            auto maximizedHeight = 0.0;
+            if (res.HasKey(windowedHeightKey))
+            {
+                const auto valFromResources = res.Lookup(windowedHeightKey);
+                windowedHeight = winrt::unbox_value_or<double>(valFromResources, 0.0);
+            }
+            if (res.HasKey(maximizedHeightKey))
+            {
+                const auto valFromResources = res.Lookup(maximizedHeightKey);
+                maximizedHeight = winrt::unbox_value_or<double>(valFromResources, 0.0);
+            }
+            return std::tuple<double, double>{ windowedHeight, maximizedHeight };
+        }();
+        static const auto windowedHeight = std::get<0>(heights);
+        static const auto maximizedHeight = std::get<1>(heights);
+
+        switch (visualState)
+        {
+        case WindowVisualState::WindowVisualStateMaximized:
+            CaptionButtonSpace().Height(maximizedHeight);
+            break;
+
+        case WindowVisualState::WindowVisualStateNormal:
+        case WindowVisualState::WindowVisualStateIconified:
+        default:
+            CaptionButtonSpace().Height(windowedHeight);
+            break;
+        }
     }
 
     // GH#9443: HoverButton, PressButton, ClickButton and ReleaseButtons are all
     // used to manually interact with the buttons, in the same way that XAML
     // would normally send events.
 
-    void TitlebarControl::HoverButton(CaptionButton button)
+    void TitlebarControl::HoverButton(CaptionButton /*button*/)
     {
-        MinMaxCloseControl().HoverButton(button);
+        // MinMaxCloseControl().HoverButton(button);
     }
-    void TitlebarControl::PressButton(CaptionButton button)
+    void TitlebarControl::PressButton(CaptionButton /*button*/)
     {
-        MinMaxCloseControl().PressButton(button);
+        // MinMaxCloseControl().PressButton(button);
     }
     winrt::fire_and_forget TitlebarControl::ClickButton(CaptionButton button)
     {
@@ -120,7 +162,7 @@ namespace winrt::TerminalApp::implementation
         // the "Hovered" state when we minimize. This will leave the button
         // visibly hovered in the taskbar preview for our window.
         auto weakThis{ get_weak() };
-        co_await MinMaxCloseControl().Dispatcher();
+        co_await CaptionButtonSpace().Dispatcher();
         if (auto self{ weakThis.get() })
         {
             // Just handle this in the same way we would if the button were
@@ -141,7 +183,7 @@ namespace winrt::TerminalApp::implementation
     }
     void TitlebarControl::ReleaseButtons()
     {
-        MinMaxCloseControl().ReleaseButtons();
+        // MinMaxCloseControl().ReleaseButtons();
     }
 
 }

src/cascadia/TerminalApp/TitlebarControl.xaml

@@ -13,7 +13,6 @@
       VerticalAlignment="Top"
       d:DesignHeight="36"
       d:DesignWidth="400"
-      Background="{ThemeResource TabViewBackground}"
       SizeChanged="Root_SizeChanged"
       mc:Ignorable="d">
 
@@ -26,6 +25,26 @@
         accent color. (which is GH#1963)
     -->
 
+
+    <Grid.Resources>
+        <ResourceDictionary>
+            <!--
+                "CaptionButtonHeightWindowed" and
+                "CaptionButtonHeightMaximized" define the size we should use
+                for the caption buttons height for the windowed and maximized
+                states, respectively.
+                
+                32 was chosen for the Maximized height to match the height of
+                the TabRowControl. This way, when the window is maximized, the
+                tabs will be flush with the top of the window. See GH#2541 for
+                details.
+            -->
+            <x:Double x:Key="CaptionButtonHeightWindowed">40.0</x:Double>
+            <!--  32 + 1 to compensate for GH#10746  -->
+            <x:Double x:Key="CaptionButtonHeightMaximized">33.0</x:Double>
+        </ResourceDictionary>
+    </Grid.Resources>
+
     <Grid.ColumnDefinitions>
         <ColumnDefinition Width="Auto" />
         <ColumnDefinition Width="*" />
@@ -40,9 +59,15 @@
             MinWidth="45.0"
             DoubleTapped="DragBar_DoubleTapped" />
 
-    <local:MinMaxCloseControl x:Name="MinMaxCloseControl"
+    <!--     <local:MinMaxCloseControl x:Name="MinMaxCloseControl"
                               Grid.Column="2"
-                              HorizontalAlignment="Right" />
+                              HorizontalAlignment="Right" />-->
+
+    <Border x:Name="CaptionButtonSpace"
+            Grid.Column="2"
+            Height="{StaticResource CaptionButtonHeightWindowed}"
+            MinWidth="138.0"
+            Background="Transparent" />
 
     <!--  This border needs to be added manually until GH#10320 is fixed  -->
     <Border Grid.Column="1"

src/cascadia/TerminalControl/TermControl.cpp

@@ -503,6 +503,8 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
             RootGrid().Background(solidColor);
         }
+
+        BackgroundBrush(RootGrid().Background());
     }
 
     // Method Description:

src/cascadia/TerminalControl/TermControl.h

@@ -117,6 +117,8 @@ namespace winrt::Microsoft::Terminal::Control::implementation
 
         void AdjustOpacity(const double opacity, const bool relative);
 
+        WINRT_CALLBACK(PropertyChanged, Windows::UI::Xaml::Data::PropertyChangedEventHandler);
+
         // -------------------------------- WinRT Events ---------------------------------
         // clang-format off
         WINRT_CALLBACK(FontSizeChanged, Control::FontSizeChangedEventArgs);
@@ -140,6 +142,8 @@ namespace winrt::Microsoft::Terminal::Control::implementation
         TYPED_EVENT(WarningBell,               IInspectable, IInspectable);
         // clang-format on
 
+        WINRT_OBSERVABLE_PROPERTY(winrt::Windows::UI::Xaml::Media::Brush, BackgroundBrush, _PropertyChangedHandlers, nullptr);
+
     private:
         friend struct TermControlT<TermControl>; // friend our parent so it can bind private event handlers
 

src/cascadia/TerminalControl/TermControl.idl

@@ -14,7 +14,8 @@ namespace Microsoft.Terminal.Control
     [default_interface] runtimeclass TermControl : Windows.UI.Xaml.Controls.UserControl,
                                                    IDirectKeyListener,
                                                    IMouseWheelListener,
-                                                   ICoreState
+                                                   ICoreState,
+                                                   Windows.UI.Xaml.Data.INotifyPropertyChanged
     {
         TermControl(IControlSettings settings,
                     IControlAppearance unfocusedAppearance,
@@ -85,5 +86,6 @@ namespace Microsoft.Terminal.Control
         // opacity set by the settings should call this instead.
         Double BackgroundOpacity { get; };
 
+        Windows.UI.Xaml.Media.Brush BackgroundBrush { get; };
     }
 }

src/cascadia/TerminalSettingsEditor/GlobalAppearance.cpp

@@ -41,17 +41,18 @@ namespace winrt::Microsoft::Terminal::Settings::Editor::implementation
         L"zh-Hant-TW",
     };
 
-    GlobalAppearance::GlobalAppearance()
+    GlobalAppearance::GlobalAppearance() :
+        _ThemeList{ single_threaded_observable_vector<Model::Theme>() }
     {
         InitializeComponent();
 
-        INITIALIZE_BINDABLE_ENUM_SETTING(Theme, ElementTheme, winrt::Windows::UI::Xaml::ElementTheme, L"Globals_Theme", L"Content");
         INITIALIZE_BINDABLE_ENUM_SETTING(TabWidthMode, TabViewWidthMode, winrt::Microsoft::UI::Xaml::Controls::TabViewWidthMode, L"Globals_TabWidthMode", L"Content");
     }
 
     void GlobalAppearance::OnNavigatedTo(const NavigationEventArgs& e)
     {
         _State = e.Parameter().as<Editor::GlobalAppearancePageNavigationState>();
+        _UpdateThemeList();
     }
 
     winrt::hstring GlobalAppearance::LanguageDisplayConverter(const winrt::hstring& tag)
@@ -195,4 +196,66 @@ namespace winrt::Microsoft::Terminal::Settings::Editor::implementation
         }
     }
 
+    // Function Description:
+    // - Updates the list of all themes available to choose from.
+    void GlobalAppearance::_UpdateThemeList()
+    {
+        // Surprisingly, though this is called every time we navigate to the page,
+        // the list does not keep growing on each navigation.
+        const auto& ThemeMap{ _State.Globals().Themes() };
+        for (const auto& pair : ThemeMap)
+        {
+            const auto& theme{ pair.Value() };
+            const auto& name{ theme.Name() };
+            theme;
+            name;
+
+            _ThemeList.Append(theme);
+        }
+    }
+
+    winrt::Windows::Foundation::IInspectable GlobalAppearance::CurrentTheme()
+    {
+        return _State.Globals().CurrentTheme();
+    }
+
+    // Get the name out of the newly selected item, stash that as the Theme name
+    // set for the globals. That controls which theme is actually the current
+    // theme.
+    void GlobalAppearance::CurrentTheme(const winrt::Windows::Foundation::IInspectable& tag)
+    {
+        if (const auto& theme{ tag.try_as<Model::Theme>() })
+        {
+            _State.Globals().Theme(theme.Name());
+        }
+    }
+
+    // Method Description:
+    // - Convert the names of the inbox themes to some more descriptive,
+    //   well-known values. If the passed in theme isn't an inbox one, then just
+    //   return its set Name.
+    //    - "light" becomes "Light"
+    //    - "dark" becomes "Dark"
+    //    - "system" becomes "Use Windows theme"
+    // - These values are all localized based on the app language.
+    // Arguments:
+    // - theme: the theme to get the display name for.
+    // Return Value:
+    // - the potentially localized name to use for this Theme.
+    winrt::hstring GlobalAppearance::WellKnownThemeNameConverter(const Model::Theme& theme)
+    {
+        if (theme.Name() == L"dark")
+        {
+            return RS_(L"Globals_ThemeDark/Content");
+        }
+        if (theme.Name() == L"light")
+        {
+            return RS_(L"Globals_ThemeLight/Content");
+        }
+        if (theme.Name() == L"system")
+        {
+            return RS_(L"Globals_ThemeSystem/Content");
+        }
+        return theme.Name();
+    }
 }

src/cascadia/TerminalSettingsEditor/GlobalAppearance.h

@@ -26,9 +26,10 @@ namespace winrt::Microsoft::Terminal::Settings::Editor::implementation
         void OnNavigatedTo(const winrt::Windows::UI::Xaml::Navigation::NavigationEventArgs& e);
 
         WINRT_PROPERTY(Editor::GlobalAppearancePageNavigationState, State, nullptr);
-        GETSET_BINDABLE_ENUM_SETTING(Theme, winrt::Windows::UI::Xaml::ElementTheme, State().Globals().Theme);
         GETSET_BINDABLE_ENUM_SETTING(TabWidthMode, winrt::Microsoft::UI::Xaml::Controls::TabViewWidthMode, State().Globals().TabWidthMode);
 
+        WINRT_PROPERTY(Windows::Foundation::Collections::IObservableVector<Model::Theme>, ThemeList, nullptr);
+
     public:
         // LanguageDisplayConverter maps the given BCP 47 tag to a localized string.
         // For instance "en-US" produces "English (United States)", while "de-DE" produces
@@ -40,9 +41,16 @@ namespace winrt::Microsoft::Terminal::Settings::Editor::implementation
         winrt::Windows::Foundation::IInspectable CurrentLanguage();
         void CurrentLanguage(const winrt::Windows::Foundation::IInspectable& tag);
 
+        winrt::Windows::Foundation::IInspectable CurrentTheme();
+        void CurrentTheme(const winrt::Windows::Foundation::IInspectable& tag);
+        static winrt::hstring WellKnownThemeNameConverter(const Model::Theme& theme);
+
     private:
         winrt::Windows::Foundation::Collections::IObservableVector<winrt::hstring> _languageList;
         winrt::Windows::Foundation::IInspectable _currentLanguage;
+        winrt::Windows::Foundation::IInspectable _currentTheme;
+
+        void _UpdateThemeList();
     };
 }
 

src/cascadia/TerminalSettingsEditor/GlobalAppearance.idl

@@ -21,7 +21,8 @@ namespace Microsoft.Terminal.Settings.Editor
         IInspectable CurrentLanguage;
 
         IInspectable CurrentTheme;
-        Windows.Foundation.Collections.IObservableVector<Microsoft.Terminal.Settings.Editor.EnumEntry> ThemeList { get; };
+        static String WellKnownThemeNameConverter(Microsoft.Terminal.Settings.Model.Theme theme);
+        Windows.Foundation.Collections.IObservableVector<Microsoft.Terminal.Settings.Model.Theme> ThemeList { get; };
 
         IInspectable CurrentTabWidthMode;
         Windows.Foundation.Collections.IObservableVector<Microsoft.Terminal.Settings.Editor.EnumEntry> TabWidthModeList { get; };

src/cascadia/TerminalSettingsEditor/GlobalAppearance.xaml

@@ -8,6 +8,7 @@
       xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
       xmlns:local="using:Microsoft.Terminal.Settings.Editor"
       xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+      xmlns:model="using:Microsoft.Terminal.Settings.Model"
       xmlns:muxc="using:Microsoft.UI.Xaml.Controls"
       mc:Ignorable="d">
 
@@ -42,10 +43,15 @@
             <!--  Theme  -->
             <local:SettingContainer x:Uid="Globals_Theme">
                 <ComboBox AutomationProperties.AccessibilityView="Content"
-                          ItemTemplate="{StaticResource EnumComboBoxTemplate}"
                           ItemsSource="{x:Bind ThemeList, Mode=OneWay}"
                           SelectedItem="{x:Bind CurrentTheme, Mode=TwoWay}"
-                          Style="{StaticResource ComboBoxSettingStyle}" />
+                          Style="{StaticResource ComboBoxSettingStyle}">
+                    <ComboBox.ItemTemplate>
+                        <DataTemplate x:DataType="model:Theme">
+                            <TextBlock Text="{x:Bind local:GlobalAppearance.WellKnownThemeNameConverter((model:Theme)), Mode=OneWay}" />
+                        </DataTemplate>
+                    </ComboBox.ItemTemplate>
+                </ComboBox>
             </local:SettingContainer>
 
             <!--  Always show tabs  -->

src/cascadia/TerminalSettingsModel/CascadiaSettings.h

@@ -73,6 +73,7 @@ namespace winrt::Microsoft::Terminal::Settings::Model::implementation
             const Json::Value& colorSchemes;
             const Json::Value& profileDefaults;
             const Json::Value& profilesList;
+            const Json::Value& themes;
         };
 
         static std::pair<size_t, size_t> _lineAndColumnFromPosition(const std::string_view& string, const size_t position);

src/cascadia/TerminalSettingsModel/CascadiaSettingsSerialization.cpp

@@ -39,6 +39,7 @@ static constexpr std::string_view ProfilesKey{ "profiles" };
 static constexpr std::string_view DefaultSettingsKey{ "defaults" };
 static constexpr std::string_view ProfilesListKey{ "list" };
 static constexpr std::string_view SchemesKey{ "schemes" };
+static constexpr std::string_view ThemesKey{ "themes" };
 
 static constexpr std::wstring_view jsonExtension{ L".json" };
 static constexpr std::wstring_view FragmentsSubDirectory{ L"\\Fragments" };
@@ -529,6 +530,23 @@ void SettingsLoader::_parse(const OriginTag origin, const winrt::hstring& source
         }
     }
 
+    {
+        for (const auto& themeJson : json.themes)
+        {
+            if (const auto theme = Theme::FromJson(themeJson))
+            {
+                if (origin != OriginTag::InBox &&
+                    (theme->Name() == L"system" || theme->Name() == L"light" || theme->Name() == L"dark"))
+                {
+                    // If the theme didn't come from the in box themes, and it's
+                    // name was one of the reserved names, then just ignore it.
+                    continue;
+                }
+                settings.globals->AddTheme(*theme);
+            }
+        }
+    }
+
     {
         settings.baseLayerProfile = Profile::FromJson(json.profileDefaults);
         // Remove the `guid` member from the default settings.
@@ -627,10 +645,11 @@ SettingsLoader::JsonSettings SettingsLoader::_parseJson(const std::string_view&
 {
     auto root = content.empty() ? Json::Value{ Json::ValueType::objectValue } : _parseJSON(content);
     const auto& colorSchemes = _getJSONValue(root, SchemesKey);
+    const auto& themes = _getJSONValue(root, ThemesKey);
     const auto& profilesObject = _getJSONValue(root, ProfilesKey);
     const auto& profileDefaults = _getJSONValue(profilesObject, DefaultSettingsKey);
     const auto& profilesList = profilesObject.isArray() ? profilesObject : _getJSONValue(profilesObject, ProfilesListKey);
-    return JsonSettings{ std::move(root), colorSchemes, profileDefaults, profilesList };
+    return JsonSettings{ std::move(root), colorSchemes, profileDefaults, profilesList, themes };
 }
 
 // Just a common helper function between _parse and _parseFragment.
@@ -1055,6 +1074,20 @@ Json::Value CascadiaSettings::ToJson() const
     }
     json[JsonKey(SchemesKey)] = schemes;
 
+    Json::Value themes{ Json::ValueType::arrayValue };
+    for (const auto& entry : _globals->Themes())
+    {
+        // Ignore the built in themes, when serializing the themes back out. We
+        // don't want to re-include them in the user settings file.
+        const auto theme{ winrt::get_self<Theme>(entry.Value()) };
+        if (theme->Name() == L"system" || theme->Name() == L"light" || theme->Name() == L"dark")
+        {
+            continue;
+        }
+        themes.append(theme->ToJson());
+    }
+    json[JsonKey(ThemesKey)] = themes;
+
     return json;
 }
 

src/cascadia/TerminalSettingsModel/GlobalAppSettings.cpp

@@ -17,6 +17,7 @@ using namespace winrt::Microsoft::UI::Xaml::Controls;
 
 static constexpr std::string_view LegacyKeybindingsKey{ "keybindings" };
 static constexpr std::string_view ActionsKey{ "actions" };
+static constexpr std::string_view ThemeKey{ "theme" };
 static constexpr std::string_view DefaultProfileKey{ "defaultProfile" };
 static constexpr std::string_view LegacyUseTabSwitcherModeKey{ "useTabSwitcher" };
 
@@ -39,6 +40,14 @@ void GlobalAppSettings::_FinalizeInheritance()
                 _colorSchemes.Insert(k, v);
             }
         }
+
+        for (const auto& [k, v] : parent->_themes)
+        {
+            if (!_themes.HasKey(k))
+            {
+                _themes.Insert(k, v);
+            }
+        }
     }
 }
 
@@ -65,6 +74,14 @@ winrt::com_ptr<GlobalAppSettings> GlobalAppSettings::Copy() const
             globals->_colorSchemes.Insert(kv.Key(), *schemeImpl->Copy());
         }
     }
+    if (_themes)
+    {
+        for (auto kv : _themes)
+        {
+            const auto themeImpl{ winrt::get_self<implementation::Theme>(kv.Value()) };
+            globals->_themes.Insert(kv.Key(), *themeImpl->Copy());
+        }
+    }
 
     for (const auto& parent : _parents)
     {
@@ -192,3 +209,17 @@ Json::Value GlobalAppSettings::ToJson() const
     json[JsonKey(ActionsKey)] = _actionMap->ToJson();
     return json;
 }
+
+winrt::Microsoft::Terminal::Settings::Model::Theme GlobalAppSettings::CurrentTheme() noexcept
+{
+    return _themes.HasKey(Theme()) ? _themes.Lookup(Theme()) : nullptr;
+}
+void GlobalAppSettings::AddTheme(const Model::Theme& theme)
+{
+    _themes.Insert(theme.Name(), theme);
+}
+
+winrt::Windows::Foundation::Collections::IMapView<winrt::hstring, winrt::Microsoft::Terminal::Settings::Model::Theme> GlobalAppSettings::Themes() noexcept
+{
+    return _themes.GetView();
+}

src/cascadia/TerminalSettingsModel/GlobalAppSettings.h

@@ -22,6 +22,7 @@ Author(s):
 #include "ActionMap.h"
 #include "Command.h"
 #include "ColorScheme.h"
+#include "Theme.h"
 
 // fwdecl unittest classes
 namespace SettingsModelLocalTests
@@ -62,6 +63,10 @@ namespace winrt::Microsoft::Terminal::Settings::Model::implementation
             DisableAnimations(!invertedDisableAnimationsValue);
         }
 
+        Windows::Foundation::Collections::IMapView<hstring, Model::Theme> Themes() noexcept;
+        void AddTheme(const Model::Theme& theme);
+        Model::Theme CurrentTheme() noexcept;
+
         INHERITABLE_SETTING(Model::GlobalAppSettings, hstring, UnparsedDefaultProfile, L"");
 
 #define GLOBAL_SETTINGS_INITIALIZE(type, name, jsonKey, ...) \
@@ -78,7 +83,9 @@ namespace winrt::Microsoft::Terminal::Settings::Model::implementation
 
         winrt::guid _defaultProfile;
         winrt::com_ptr<implementation::ActionMap> _actionMap{ winrt::make_self<implementation::ActionMap>() };
+
         std::vector<SettingsLoadWarnings> _keybindingsWarnings;
         Windows::Foundation::Collections::IMap<winrt::hstring, Model::ColorScheme> _colorSchemes{ winrt::single_threaded_map<winrt::hstring, Model::ColorScheme>() };
+        Windows::Foundation::Collections::IMap<winrt::hstring, Model::Theme> _themes{ winrt::single_threaded_map<winrt::hstring, Model::Theme>() };
     };
 }

src/cascadia/TerminalSettingsModel/GlobalAppSettings.idl

@@ -3,6 +3,7 @@
 
 #include "IInheritable.idl.h"
 
+import "Theme.idl";
 import "ColorScheme.idl";
 import "ActionMap.idl";
 
@@ -54,7 +55,6 @@ namespace Microsoft.Terminal.Settings.Model
         INHERITABLE_SETTING(Boolean, ShowTitleInTitlebar);
         INHERITABLE_SETTING(Boolean, ConfirmCloseAllTabs);
         INHERITABLE_SETTING(String, Language);
-        INHERITABLE_SETTING(Windows.UI.Xaml.ElementTheme, Theme);
         INHERITABLE_SETTING(Microsoft.UI.Xaml.Controls.TabViewWidthMode, TabWidthMode);
         INHERITABLE_SETTING(Boolean, UseAcrylicInTabRow);
         INHERITABLE_SETTING(Boolean, ShowTabsInTitlebar);
@@ -94,5 +94,10 @@ namespace Microsoft.Terminal.Settings.Model
         void RemoveColorScheme(String schemeName);
 
         ActionMap ActionMap { get; };
+
+        Windows.Foundation.Collections.IMapView<String, Theme> Themes();
+        void AddTheme(Theme theme);
+        INHERITABLE_SETTING(String, Theme);
+        Theme CurrentTheme { get; };
     }
 }

src/cascadia/TerminalSettingsModel/MTSMSettings.h

@@ -33,8 +33,8 @@ Author(s):
     X(bool, AlwaysShowTabs, "alwaysShowTabs", true)                                                                                                        \
     X(bool, ShowTitleInTitlebar, "showTerminalTitleInTitlebar", true)                                                                                      \
     X(bool, ConfirmCloseAllTabs, "confirmCloseAllTabs", true)                                                                                              \
+    X(hstring, Theme, "theme")                                                                                                                             \
     X(hstring, Language, "language")                                                                                                                       \
-    X(winrt::Windows::UI::Xaml::ElementTheme, Theme, "theme", winrt::Windows::UI::Xaml::ElementTheme::Default)                                             \
     X(winrt::Microsoft::UI::Xaml::Controls::TabViewWidthMode, TabWidthMode, "tabWidthMode", winrt::Microsoft::UI::Xaml::Controls::TabViewWidthMode::Equal) \
     X(bool, UseAcrylicInTabRow, "useAcrylicInTabRow", false)                                                                                               \
     X(bool, ShowTabsInTitlebar, "showTabsInTitlebar", true)                                                                                                \
@@ -112,3 +112,14 @@ Author(s):
 // Intentionally omitted Appearance settings:
 // * ForegroundKey, BackgroundKey, SelectionBackgroundKey, CursorColorKey: all optional colors
 // * Opacity: needs special parsing
+
+#define MTSM_THEME_SETTINGS(X)                                                             \
+    X(winrt::Microsoft::Terminal::Settings::Model::WindowTheme, Window, "window", nullptr) \
+    X(winrt::Microsoft::Terminal::Settings::Model::TabRowTheme, TabRow, "tabRow", nullptr)
+
+#define MTSM_THEME_WINDOW_SETTINGS(X)                                                                                              \
+    X(winrt::Windows::UI::Xaml::ElementTheme, RequestedTheme, "applicationTheme", winrt::Windows::UI::Xaml::ElementTheme::Default) \
+    X(bool, UseMica, "useMica", false)
+
+#define MTSM_THEME_TABROW_SETTINGS(X) \
+    X(winrt::Microsoft::Terminal::Settings::Model::ThemeColor, Background, "background", nullptr)

src/cascadia/TerminalSettingsModel/Microsoft.Terminal.Settings.ModelLib.vcxproj

@@ -48,6 +48,9 @@
     <ClInclude Include="ColorScheme.h">
       <DependentUpon>ColorScheme.idl</DependentUpon>
     </ClInclude>
+    <ClInclude Include="Theme.h">
+      <DependentUpon>Theme.idl</DependentUpon>
+    </ClInclude>
     <ClInclude Include="Command.h">
       <DependentUpon>Command.idl</DependentUpon>
     </ClInclude>
@@ -128,6 +131,9 @@
     <ClCompile Include="ColorScheme.cpp">
       <DependentUpon>ColorScheme.idl</DependentUpon>
     </ClCompile>
+    <ClCompile Include="Theme.cpp">
+      <DependentUpon>Theme.idl</DependentUpon>
+    </ClCompile>
     <ClCompile Include="Command.cpp">
       <DependentUpon>Command.idl</DependentUpon>
     </ClCompile>
@@ -173,6 +179,7 @@
     <Midl Include="ApplicationState.idl" />
     <Midl Include="CascadiaSettings.idl" />
     <Midl Include="ColorScheme.idl" />
+    <Midl Include="Theme.idl" />
     <Midl Include="Command.idl" />
     <Midl Include="DefaultTerminal.idl" />
     <Midl Include="GlobalAppSettings.idl" />

src/cascadia/TerminalSettingsModel/TerminalSettingsSerializationHelpers.h

@@ -546,3 +546,63 @@ JSON_ENUM_MAPPER(::winrt::Microsoft::Terminal::Settings::Model::InfoBarMessage)
         pair_type{ "setAsDefault", ValueType::SetAsDefault },
     };
 };
+
+template<>
+struct ::Microsoft::Terminal::Settings::Model::JsonUtils::ConversionTrait<winrt::Microsoft::Terminal::Settings::Model::ThemeColor>
+{
+    winrt::Microsoft::Terminal::Settings::Model::ThemeColor FromJson(const Json::Value& json)
+    {
+        const auto string{ Detail::GetStringView(json) };
+        if (string == "accent")
+        {
+            return winrt::Microsoft::Terminal::Settings::Model::ThemeColor::FromAccent();
+        }
+        else if (string == "terminalBackground")
+        {
+            return winrt::Microsoft::Terminal::Settings::Model::ThemeColor::FromTerminalBackground();
+        }
+        else
+        {
+            return winrt::Microsoft::Terminal::Settings::Model::ThemeColor::FromColor(::Microsoft::Console::Utils::ColorFromHexString(string));
+        }
+    }
+
+    bool CanConvert(const Json::Value& json)
+    {
+        if (!json.isString())
+        {
+            return false;
+        }
+
+        const auto string{ Detail::GetStringView(json) };
+        const auto isColorSpec = (string.length() == 9 || string.length() == 7 || string.length() == 4) && string.front() == '#';
+        const auto isAccent = string == "accent";
+        const auto isTerminalBackground = string == "terminalBackground";
+        return isColorSpec || isAccent || isTerminalBackground;
+    }
+
+    Json::Value ToJson(const winrt::Microsoft::Terminal::Settings::Model::ThemeColor& val)
+    {
+        switch (val.ColorType())
+        {
+        case winrt::Microsoft::Terminal::Settings::Model::ThemeColorType::Accent:
+        {
+            return "accent";
+        }
+        case winrt::Microsoft::Terminal::Settings::Model::ThemeColorType::Color:
+        {
+            return til::u16u8(til::color{ val.Color() }.ToHexString(false));
+        }
+        case winrt::Microsoft::Terminal::Settings::Model::ThemeColorType::TerminalBackground:
+        {
+            return "terminalBackground";
+        }
+        }
+        return til::u16u8(til::color{ val.Color() }.ToHexString(false));
+    }
+
+    std::string TypeDescription() const
+    {
+        return "ThemeColor (#rrggbb, #rgb, #aarrggbb, accent, terminalBackground)";
+    }
+};

src/cascadia/TerminalSettingsModel/Theme.cpp

@@ -0,0 +1,263 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
+#include "pch.h"
+#include "Theme.h"
+#include "../../types/inc/Utils.hpp"
+#include "../../types/inc/colorTable.hpp"
+#include "Utils.h"
+#include "JsonUtils.h"
+#include "TerminalSettingsSerializationHelpers.h"
+
+#include "ThemeColor.g.cpp"
+#include "WindowTheme.g.cpp"
+#include "TabRowTheme.g.cpp"
+#include "Theme.g.cpp"
+
+using namespace ::Microsoft::Console;
+using namespace Microsoft::Terminal::Settings::Model;
+using namespace winrt::Microsoft::Terminal::Settings::Model::implementation;
+using namespace winrt::Windows::UI;
+
+static constexpr std::string_view NameKey{ "name" };
+
+static constexpr wchar_t RegKeyDwm[] = L"Software\\Microsoft\\Windows\\DWM";
+static constexpr wchar_t RegKeyAccentColor[] = L"AccentColor";
+
+winrt::Microsoft::Terminal::Settings::Model::ThemeColor ThemeColor::FromColor(const winrt::Microsoft::Terminal::Core::Color& coreColor) noexcept
+{
+    auto result = winrt::make_self<implementation::ThemeColor>();
+    result->_Color = coreColor;
+    result->_ColorType = ThemeColorType::Color;
+    return *result;
+}
+
+winrt::Microsoft::Terminal::Settings::Model::ThemeColor ThemeColor::FromAccent() noexcept
+{
+    auto result = winrt::make_self<implementation::ThemeColor>();
+    result->_ColorType = ThemeColorType::Accent;
+    return *result;
+}
+
+winrt::Microsoft::Terminal::Settings::Model::ThemeColor ThemeColor::FromTerminalBackground() noexcept
+{
+    auto result = winrt::make_self<implementation::ThemeColor>();
+    result->_ColorType = ThemeColorType::TerminalBackground;
+    return *result;
+}
+
+static wil::unique_hkey openDwmRegKey()
+{
+    HKEY hKey{ nullptr };
+    if (RegOpenKeyEx(HKEY_CURRENT_USER, RegKeyDwm, 0, KEY_READ, &hKey) == ERROR_SUCCESS)
+    {
+        return wil::unique_hkey{ hKey };
+    }
+    return nullptr;
+}
+static DWORD readDwmSubValue(const wil::unique_hkey& dwmRootKey, const wchar_t* key)
+{
+    DWORD val{ 0 };
+    DWORD size{ sizeof(val) };
+    LOG_IF_FAILED(RegQueryValueExW(dwmRootKey.get(), key, nullptr, nullptr, reinterpret_cast<BYTE*>(&val), &size));
+    return val;
+}
+
+static til::color _getAccentColorForTitlebar()
+{
+    return til::color{ static_cast<COLORREF>(readDwmSubValue(openDwmRegKey(), RegKeyAccentColor)) };
+}
+
+til::color ThemeColor::ColorFromBrush(const winrt::Windows::UI::Xaml::Media::Brush& brush)
+{
+    if (auto acrylic = brush.try_as<winrt::Windows::UI::Xaml::Media::AcrylicBrush>())
+    {
+        return acrylic.TintColor();
+    }
+    else if (auto solidColor = brush.try_as<winrt::Windows::UI::Xaml::Media::SolidColorBrush>())
+    {
+        return solidColor.Color();
+    }
+    return {};
+}
+
+winrt::Windows::UI::Xaml::Media::Brush ThemeColor::Evaluate(const winrt::Windows::UI::Xaml::ResourceDictionary& res,
+                                                            const winrt::Windows::UI::Xaml::Media::Brush& terminalBackground,
+                                                            const bool forTitlebar)
+{
+    static const auto accentColorKey{ winrt::box_value(L"SystemAccentColor") };
+
+    switch (ColorType())
+    {
+    case ThemeColorType::Accent:
+    {
+        til::color accentColor;
+        if (forTitlebar)
+        {
+            accentColor = _getAccentColorForTitlebar();
+        }
+        else
+        {
+            accentColor = winrt::unbox_value<winrt::Windows::UI::Color>(res.Lookup(accentColorKey));
+        }
+
+        const auto accentBrush = winrt::Windows::UI::Xaml::Media::SolidColorBrush();
+        accentBrush.Color(accentColor);
+        return accentBrush;
+    }
+    case ThemeColorType::Color:
+    {
+        const auto solidBrush = winrt::Windows::UI::Xaml::Media::SolidColorBrush();
+        solidBrush.Color(Color());
+        return solidBrush;
+    }
+    case ThemeColorType::TerminalBackground:
+    {
+        return terminalBackground;
+    }
+    }
+    return nullptr;
+}
+
+#define THEME_SETTINGS_FROM_JSON(type, name, jsonKey, ...) \
+    result->name(JsonUtils::GetValueForKey<type>(json, jsonKey));
+
+#define THEME_SETTINGS_TO_JSON(type, name, jsonKey, ...) \
+    JsonUtils::SetValueForKey(json, jsonKey, val.name());
+
+#define THEME_OBJECT_CONVERTER(nameSpace, name, macro)                                         \
+    template<>                                                                                 \
+    struct ::Microsoft::Terminal::Settings::Model::JsonUtils::ConversionTrait<nameSpace::name> \
+    {                                                                                          \
+        nameSpace::name FromJson(const Json::Value& json)                                      \
+        {                                                                                      \
+            auto result = winrt::make_self<nameSpace::implementation::name>();                 \
+            macro(THEME_SETTINGS_FROM_JSON);                                                   \
+            return *result;                                                                    \
+        }                                                                                      \
+                                                                                               \
+        bool CanConvert(const Json::Value& json)                                               \
+        {                                                                                      \
+            return json.isObject();                                                            \
+        }                                                                                      \
+                                                                                               \
+        Json::Value ToJson(const nameSpace::name& val)                                         \
+        {                                                                                      \
+            if (val == nullptr)                                                                \
+                return Json::Value::null;                                                      \
+            Json::Value json{ Json::ValueType::objectValue };                                  \
+            macro(THEME_SETTINGS_TO_JSON);                                                     \
+            return json;                                                                       \
+        }                                                                                      \
+                                                                                               \
+        std::string TypeDescription() const                                                    \
+        {                                                                                      \
+            return "name (You should never see this)";                                         \
+        }                                                                                      \
+    };
+
+THEME_OBJECT_CONVERTER(winrt::Microsoft::Terminal::Settings::Model, WindowTheme, MTSM_THEME_WINDOW_SETTINGS);
+THEME_OBJECT_CONVERTER(winrt::Microsoft::Terminal::Settings::Model, TabRowTheme, MTSM_THEME_TABROW_SETTINGS);
+
+#undef THEME_SETTINGS_FROM_JSON
+#undef THEME_SETTINGS_TO_JSON
+#undef THEME_OBJECT_CONVERTER
+
+Theme::Theme() noexcept :
+    Theme{ winrt::Windows::UI::Xaml::ElementTheme::Default }
+{
+}
+
+Theme::Theme(const winrt::Windows::UI::Xaml::ElementTheme& requestedTheme) noexcept
+{
+    auto window{ winrt::make_self<implementation::WindowTheme>() };
+    window->RequestedTheme(requestedTheme);
+    _Window = *window;
+}
+
+winrt::com_ptr<Theme> Theme::Copy() const
+{
+    auto theme{ winrt::make_self<Theme>() };
+
+    theme->_Name = _Name;
+
+    if (_Window)
+    {
+        theme->_Window = *winrt::get_self<implementation::WindowTheme>(_Window)->Copy();
+    }
+    if (_TabRow)
+    {
+        theme->_TabRow = *winrt::get_self<implementation::TabRowTheme>(_TabRow)->Copy();
+    }
+
+    return theme;
+}
+
+// Method Description:
+// - Create a new instance of this class from a serialized JsonObject.
+// Arguments:
+// - json: an object which should be a serialization of a ColorScheme object.
+// Return Value:
+// - Returns nullptr for invalid JSON.
+winrt::com_ptr<Theme> Theme::FromJson(const Json::Value& json)
+{
+    auto result = winrt::make_self<Theme>();
+    result->LayerJson(json);
+    return result;
+}
+
+void Theme::LayerJson(const Json::Value& json)
+{
+    if (json.isString())
+    {
+        // We found a string, not an object. Just secretly promote that string
+        // to a theme object with just the applicationTheme set from that value.
+        JsonUtils::GetValue(json, _Name);
+        winrt::Windows::UI::Xaml::ElementTheme requestedTheme{ winrt::Windows::UI::Xaml::ElementTheme::Default };
+        JsonUtils::GetValue(json, requestedTheme);
+
+        auto window{ winrt::make_self<implementation::WindowTheme>() };
+        window->RequestedTheme(requestedTheme);
+        _Window = *window;
+
+        return;
+    }
+
+    JsonUtils::GetValueForKey(json, NameKey, _Name);
+
+    // This will use each of the ConversionTrait's from above to quickly parse the sub-objects
+
+#define THEME_SETTINGS_LAYER_JSON(type, name, jsonKey, ...) \
+    JsonUtils::GetValueForKey(json, jsonKey, _##name);
+
+    MTSM_THEME_SETTINGS(THEME_SETTINGS_LAYER_JSON)
+#undef THEME_SETTINGS_LAYER_JSON
+}
+
+// Method Description:
+// - Create a new serialized JsonObject from an instance of this class
+// Arguments:
+// - <none>
+// Return Value:
+// - the JsonObject representing this instance
+Json::Value Theme::ToJson() const
+{
+    Json::Value json{ Json::ValueType::objectValue };
+
+    JsonUtils::SetValueForKey(json, NameKey, _Name);
+
+    // Don't serialize anything if the object is null.
+#define THEME_SETTINGS_TO_JSON(type, name, jsonKey, ...) \
+    if (_##name)                                         \
+        JsonUtils::SetValueForKey(json, jsonKey, _##name);
+
+    MTSM_THEME_SETTINGS(THEME_SETTINGS_TO_JSON)
+#undef THEME_SETTINGS_TO_JSON
+
+    return json;
+}
+
+winrt::hstring Theme::ToString()
+{
+    return Name();
+}

src/cascadia/TerminalSettingsModel/Theme.h

@@ -0,0 +1,108 @@
+/*++
+Copyright (c) Microsoft Corporation
+Licensed under the MIT license.
+
+Module Name:
+- Theme.hpp
+
+Abstract:
+- A Theme represents a collection of settings which control the appearance of
+  the Terminal window itself. Things like the color of the titlebar, the style
+  of the tabs.
+
+Author(s):
+- Mike Griese - March 2022
+
+--*/
+#pragma once
+
+#include "../../inc/conattrs.hpp"
+#include "DefaultSettings.h"
+#include "IInheritable.h"
+#include "MTSMSettings.h"
+
+#include "ThemeColor.g.h"
+#include "WindowTheme.g.h"
+#include "TabRowTheme.g.h"
+#include "Theme.g.h"
+
+namespace winrt::Microsoft::Terminal::Settings::Model::implementation
+{
+    struct ThemeColor : ThemeColorT<ThemeColor>
+    {
+    public:
+        ThemeColor() noexcept = default;
+        static winrt::Microsoft::Terminal::Settings::Model::ThemeColor FromColor(const winrt::Microsoft::Terminal::Core::Color& coreColor) noexcept;
+        static winrt::Microsoft::Terminal::Settings::Model::ThemeColor FromAccent() noexcept;
+        static winrt::Microsoft::Terminal::Settings::Model::ThemeColor FromTerminalBackground() noexcept;
+
+        static til::color ColorFromBrush(const winrt::Windows::UI::Xaml::Media::Brush& brush);
+
+        winrt::Windows::UI::Xaml::Media::Brush Evaluate(const winrt::Windows::UI::Xaml::ResourceDictionary& res,
+                                                        const winrt::Windows::UI::Xaml::Media::Brush& terminalBackground,
+                                                        const bool forTitlebar);
+
+        WINRT_PROPERTY(til::color, Color);
+        WINRT_PROPERTY(winrt::Microsoft::Terminal::Settings::Model::ThemeColorType, ColorType);
+    };
+
+#define THEME_SETTINGS_INITIALIZE(type, name, jsonKey, ...) \
+    WINRT_PROPERTY(type, name, ##__VA_ARGS__)
+
+#define THEME_SETTINGS_COPY(type, name, jsonKey, ...) \
+    result->_##name = _##name;
+
+#define COPY_THEME_OBJECT(T, macro)           \
+    winrt::com_ptr<T> Copy()                  \
+    {                                         \
+        auto result{ winrt::make_self<T>() }; \
+        macro(THEME_SETTINGS_COPY);           \
+        return result;                        \
+    }
+
+    struct WindowTheme : WindowThemeT<WindowTheme>
+    {
+        MTSM_THEME_WINDOW_SETTINGS(THEME_SETTINGS_INITIALIZE);
+
+    public:
+        COPY_THEME_OBJECT(WindowTheme, MTSM_THEME_WINDOW_SETTINGS);
+    };
+
+    struct TabRowTheme : TabRowThemeT<TabRowTheme>
+    {
+        MTSM_THEME_TABROW_SETTINGS(THEME_SETTINGS_INITIALIZE);
+
+    public:
+        COPY_THEME_OBJECT(TabRowTheme, MTSM_THEME_TABROW_SETTINGS);
+    };
+
+    struct Theme : ThemeT<Theme>
+    {
+    public:
+        Theme() noexcept;
+        Theme(const winrt::Windows::UI::Xaml::ElementTheme& requestedTheme) noexcept;
+
+        com_ptr<Theme> Copy() const;
+
+        hstring ToString();
+
+        static com_ptr<Theme> FromJson(const Json::Value& json);
+        void LayerJson(const Json::Value& json);
+        Json::Value ToJson() const;
+
+        WINRT_PROPERTY(winrt::hstring, Name);
+
+        MTSM_THEME_SETTINGS(THEME_SETTINGS_INITIALIZE)
+
+    private:
+    };
+
+#undef THEME_SETTINGS_INITIALIZE
+#undef THEME_SETTINGS_COPY
+}
+
+namespace winrt::Microsoft::Terminal::Settings::Model::factory_implementation
+{
+    BASIC_FACTORY(ThemeColor);
+    BASIC_FACTORY(Theme);
+}

src/cascadia/TerminalSettingsModel/Theme.idl

@@ -0,0 +1,52 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT license.
+
+namespace Microsoft.Terminal.Settings.Model
+{
+
+    enum ThemeColorType
+    {
+        Accent,
+        Color,
+        TerminalBackground
+    };
+
+    runtimeclass ThemeColor
+    {
+        ThemeColor();
+        static ThemeColor FromColor(Microsoft.Terminal.Core.Color color);
+        static ThemeColor FromAccent();
+        static ThemeColor FromTerminalBackground();
+
+        Microsoft.Terminal.Core.Color Color { get; };
+        ThemeColorType ColorType;
+
+        static Microsoft.Terminal.Core.Color ColorFromBrush(Windows.UI.Xaml.Media.Brush brush);
+        Windows.UI.Xaml.Media.Brush Evaluate(Windows.UI.Xaml.ResourceDictionary res,
+                                             Windows.UI.Xaml.Media.Brush terminalBackground,
+                                             Boolean forTitlebar);
+    }
+
+    runtimeclass WindowTheme {
+        Windows.UI.Xaml.ElementTheme RequestedTheme { get; };
+        Boolean UseMica { get; };
+    }
+
+    runtimeclass TabRowTheme {
+        ThemeColor Background { get; };
+    }
+
+    [default_interface] runtimeclass Theme : Windows.Foundation.IStringable {
+        Theme();
+        Theme(Windows.UI.Xaml.ElementTheme requestedTheme);
+
+        String Name;
+
+        // window.* Namespace
+        WindowTheme Window { get; };
+
+        // tabRow.* Namespace
+        TabRowTheme TabRow { get; };
+
+    }
+}

src/cascadia/TerminalSettingsModel/defaults.json

@@ -280,6 +280,26 @@
             "brightWhite": "#EEEEEC"
         }
     ],
+    "themes": [
+        {
+            "name": "light",
+            "window":{
+                "applicationTheme": "light"
+            }
+        },
+        {
+            "name": "dark",
+            "window":{
+                "applicationTheme": "dark"
+            }
+        },
+        {
+            "name": "system",
+            "window":{
+                "applicationTheme": "system"
+            }
+        }
+    ],
     "actions":
     [
         // Application-level Keys

src/cascadia/WindowsTerminal/AppHost.cpp

@@ -390,6 +390,11 @@ void AppHost::Initialize()
         }
     });
 
+    // Load bearing: make sure the PropertyChanged handler is added before we
+    // call Create, so that when the app sets up the titlebar brush, we're
+    // already prepared to listen for the change notification
+    _revokers.PropertyChanged = _logic.PropertyChanged(winrt::auto_revoke, { this, &AppHost::_PropertyChangedHandler });
+
     _logic.Create();
 
     _revokers.TitleChanged = _logic.TitleChanged(winrt::auto_revoke, { this, &AppHost::AppTitleChanged });
@@ -683,8 +688,12 @@ void AppHost::_UpdateTitleBarContent(const winrt::Windows::Foundation::IInspecta
 {
     if (_useNonClientArea)
     {
-        (static_cast<NonClientIslandWindow*>(_window.get()))->SetTitlebarContent(arg);
+        auto nonClientWindow{ static_cast<NonClientIslandWindow*>(_window.get()) };
+        nonClientWindow->SetTitlebarContent(arg);
+        nonClientWindow->SetTitlebarBackground(_logic.TitlebarBrush());
     }
+
+    _updateTheme();
 }
 
 // Method Description:
@@ -695,9 +704,9 @@ void AppHost::_UpdateTitleBarContent(const winrt::Windows::Foundation::IInspecta
 // - arg: the ElementTheme to use as the new theme for the UI
 // Return Value:
 // - <none>
-void AppHost::_UpdateTheme(const winrt::Windows::Foundation::IInspectable&, const winrt::Windows::UI::Xaml::ElementTheme& arg)
+void AppHost::_UpdateTheme(const winrt::Windows::Foundation::IInspectable&, const winrt::Windows::UI::Xaml::ElementTheme& /*arg*/)
 {
-    _window->OnApplicationThemeChanged(arg);
+    _updateTheme();
 }
 
 void AppHost::_FocusModeChanged(const winrt::Windows::Foundation::IInspectable&,
@@ -887,8 +896,15 @@ void AppHost::_FindTargetWindow(const winrt::Windows::Foundation::IInspectable&
     args.ResultTargetWindowName(targetWindow.WindowName());
 }
 
-winrt::fire_and_forget AppHost::_WindowActivated()
+winrt::fire_and_forget AppHost::_WindowActivated(bool activated)
 {
+    _logic.WindowActivated(activated);
+
+    if (!activated)
+    {
+        co_return;
+    }
+
     co_await winrt::resume_background();
 
     if (auto peasant{ _windowManager.CurrentWindow() })
@@ -1311,6 +1327,19 @@ winrt::fire_and_forget AppHost::_RenameWindowRequested(const winrt::Windows::Fou
     }
 }
 
+void AppHost::_updateTheme()
+{
+    auto theme = _logic.Theme();
+
+    _window->OnApplicationThemeChanged(theme.Window().RequestedTheme());
+
+    int attribute = theme.Window().UseMica() ? /* DWMSBT_MAINWINDOW */ 2 : /*DWMSBT_NONE*/ 1;
+    DwmSetWindowAttribute(_window->GetHandle(), /* DWMWA_SYSTEMBACKDROP_TYPE */ 38, &attribute, sizeof(attribute));
+
+    // COLORREF none = DWMWA_COLOR_NONE;
+    // DwmSetWindowAttribute(_window->GetHandle(), DWMWA_CAPTION_COLOR, &none, sizeof(none));
+}
+
 void AppHost::_HandleSettingsChanged(const winrt::Windows::Foundation::IInspectable& /*sender*/,
                                      const winrt::Windows::Foundation::IInspectable& /*args*/)
 {
@@ -1342,6 +1371,7 @@ void AppHost::_HandleSettingsChanged(const winrt::Windows::Foundation::IInspecta
     }
 
     _window->SetMinimizeToNotificationAreaBehavior(_logic.GetMinimizeToNotificationArea());
+    _updateTheme();
 }
 
 void AppHost::_IsQuakeWindowChanged(const winrt::Windows::Foundation::IInspectable&,
@@ -1556,3 +1586,13 @@ void AppHost::_CloseRequested(const winrt::Windows::Foundation::IInspectable& /*
     const auto pos = _GetWindowLaunchPosition();
     _logic.CloseWindow(pos);
 }
+
+void AppHost::_PropertyChangedHandler(const winrt::Windows::Foundation::IInspectable& /*sender*/,
+                                      const winrt::Windows::UI::Xaml::Data::PropertyChangedEventArgs& e)
+{
+    if (e.PropertyName() == L"TitlebarBrush")
+    {
+        auto nonClientWindow{ static_cast<NonClientIslandWindow*>(_window.get()) };
+        nonClientWindow->SetTitlebarBackground(_logic.TitlebarBrush());
+    }
+}

src/cascadia/WindowsTerminal/AppHost.h

@@ -55,7 +55,7 @@ private:
     void _RaiseVisualBell(const winrt::Windows::Foundation::IInspectable& sender,
                           const winrt::Windows::Foundation::IInspectable& arg);
     void _WindowMouseWheeled(const til::point coord, const int32_t delta);
-    winrt::fire_and_forget _WindowActivated();
+    winrt::fire_and_forget _WindowActivated(bool activated);
     void _WindowMoved();
 
     void _DispatchCommandline(winrt::Windows::Foundation::IInspectable sender,
@@ -121,6 +121,12 @@ private:
                                         const winrt::Windows::Foundation::IInspectable& args);
     void _HideNotificationIconRequested(const winrt::Windows::Foundation::IInspectable& sender,
                                         const winrt::Windows::Foundation::IInspectable& args);
+
+    void _updateTheme();
+
+    void _PropertyChangedHandler(const winrt::Windows::Foundation::IInspectable& sender,
+                                 const winrt::Windows::UI::Xaml::Data::PropertyChangedEventArgs& args);
+
     std::unique_ptr<NotificationIcon> _notificationIcon;
     winrt::event_token _ReAddNotificationIconToken;
     winrt::event_token _NotificationIconPressedToken;
@@ -164,5 +170,6 @@ private:
         winrt::Microsoft::Terminal::Remoting::WindowManager::ShowNotificationIconRequested_revoker ShowNotificationIconRequested;
         winrt::Microsoft::Terminal::Remoting::WindowManager::HideNotificationIconRequested_revoker HideNotificationIconRequested;
         winrt::Microsoft::Terminal::Remoting::WindowManager::QuitAllRequested_revoker QuitAllRequested;
+        winrt::TerminalApp::AppLogic::PropertyChanged_revoker PropertyChanged;
     } _revokers{};
 };

src/cascadia/WindowsTerminal/IslandWindow.cpp

@@ -439,10 +439,8 @@ long IslandWindow::_calculateTotalSize(const bool isWidth, const long clientSize
     case WM_ACTIVATE:
     {
         // wparam = 0 indicates the window was deactivated
-        if (LOWORD(wparam) != 0)
-        {
-            _WindowActivatedHandlers();
-        }
+        const bool activated = LOWORD(wparam) != 0;
+        _WindowActivatedHandlers(activated);
 
         break;
     }

src/cascadia/WindowsTerminal/IslandWindow.h

@@ -67,7 +67,7 @@ public:
     WINRT_CALLBACK(DragRegionClicked, winrt::delegate<>);
     WINRT_CALLBACK(WindowCloseButtonClicked, winrt::delegate<>);
     WINRT_CALLBACK(MouseScrolled, winrt::delegate<void(til::point, int32_t)>);
-    WINRT_CALLBACK(WindowActivated, winrt::delegate<void()>);
+    WINRT_CALLBACK(WindowActivated, winrt::delegate<void(bool)>);
     WINRT_CALLBACK(HotkeyPressed, winrt::delegate<void(long)>);
     WINRT_CALLBACK(NotifyNotificationIconPressed, winrt::delegate<void()>);
     WINRT_CALLBACK(NotifyWindowHidden, winrt::delegate<void()>);

src/cascadia/WindowsTerminal/NonClientIslandWindow.cpp

@@ -129,6 +129,18 @@ LRESULT NonClientIslandWindow::_dragBarNcHitTest(const til::point pointer)
     }
 }
 
+// We make the frame as tall as the XAML titlebar.
+// We get rid of the XAML caption buttons. Replace them with a transparent hole in XAML that's exactly the size of the DWM caption btns.
+// We don't extend the drag rect there, cause we don't need to anymore.
+// When we set the tabRow bg, it can't be transparent, unless mica is enabled.
+//   - If the terminal has opacity, sorry, it's opaque now.
+//   - If we want arylic titlebar, then that's ookay, make sure it's hostBackdrop
+//     - that won't apply to the DWM caption buttons tho
+//   - if we get a non host-backdrop arylic terminalBG, MAKE IT HOSTBACKDROP
+// We'd have to set the DWM caption color to match the one from the theme cause the buttons would still be drawn by DWM on that color, not us
+// we'd lose our fukin rounded maximize button, cause ofc the DWM ones don't have that
+//
+
 // Function Description:
 // - The window procedure for the drag bar forwards clicks on its client area to
 //   its parent as non-client clicks.
@@ -146,7 +158,7 @@ LRESULT NonClientIslandWindow::_dragBarNcHitTest(const til::point pointer)
 //   input via XAML.
 LRESULT NonClientIslandWindow::_InputSinkMessageHandler(UINT const message,
                                                         WPARAM const wparam,
-                                                        LPARAM const lparam) noexcept
+                                                        LPARAM lparam) noexcept
 {
     switch (message)
     {
@@ -154,7 +166,17 @@ LRESULT NonClientIslandWindow::_InputSinkMessageHandler(UINT const message,
     {
         // Try to determine what part of the window is being hovered here. This
         // is absolutely critical to making sure Snap Layouts (GH#9443) works!
-        return _dragBarNcHitTest(til::point{ GET_X_LPARAM(lparam), GET_Y_LPARAM(lparam) });
+        // return _dragBarNcHitTest(til::point{ GET_X_LPARAM(lparam), GET_Y_LPARAM(lparam) });
+        LRESULT lResult = 0;
+
+        if (!DwmDefWindowProc(GetHandle(), message, wparam, lparam, &lResult))
+        {
+            return _dragBarNcHitTest(til::point{ GET_X_LPARAM(lparam), GET_Y_LPARAM(lparam) });
+        }
+        else
+        {
+            return lResult;
+        }
     }
     break;
 
@@ -170,8 +192,12 @@ LRESULT NonClientIslandWindow::_InputSinkMessageHandler(UINT const message,
         {
         case HTTOP:
         case HTCAPTION:
+        case HTMAXBUTTON:
+        case HTMINBUTTON:
+        case HTCLOSE:
+        default:
         {
-            _titlebar.ReleaseButtons();
+            // _titlebar.ReleaseButtons();
 
             // Pass caption-related nonclient messages to the parent window.
             // Make sure to do this for the HTTOP, which is the top resize
@@ -179,43 +205,66 @@ LRESULT NonClientIslandWindow::_InputSinkMessageHandler(UINT const message,
             auto parentWindow{ GetHandle() };
             return SendMessage(parentWindow, message, wparam, lparam);
         }
-        case HTMINBUTTON:
-        case HTMAXBUTTON:
-        case HTCLOSE:
-            _titlebar.HoverButton(static_cast<winrt::TerminalApp::CaptionButton>(wparam));
-            break;
-        default:
-            _titlebar.ReleaseButtons();
-        }
+            // case HTMAXBUTTON:
+            // {
+            //     // TODO! Fake out the y coordinate here for the maximize button, so
+            //     // as to force DWM to think we've hovered on the singular visible
+            //     // pixel of the maximize button, rather than where we are, which is
+            //     // not over the caption button that DWM drew.
+            //     til::point original = til::point{ GET_X_LPARAM(lparam), GET_Y_LPARAM(lparam) };
+            //     til::rect windowRect = til::rect{ GetWindowRect() };
+            //     // auto xPos = 0xffff0000 & lparam;
+            //     auto yPos = windowRect.top + 8;
+            //     // lparam = (xPos | yPos);
+            //     lparam = MAKELONG(GET_X_LPARAM(lparam), yPos);
+            //     til::point converted = til::point{ GET_X_LPARAM(lparam), GET_Y_LPARAM(lparam) };
+            //     converted;
+            //     auto a = 0;
+            //     a++;
+            //     a;
+            //     // TODO! This didn't work at all. But _dragBarNcHitTest DOES
+            //     // successfully return the right thing. There must be some extra
+            //     // logic in the DWM side that's checking "Hey I see you said you're
+            //     // on the maximize button but the thing is, you're not"
 
-        // If we haven't previously asked for mouse tracking, request mouse
-        // tracking. We need to do this so we can get the WM_NCMOUSELEAVE
-        // message when the mouse leave the titlebar. Otherwise, we won't always
-        // get that message (especially if the user moves the mouse _real
-        // fast_).
-        if (!_trackingMouse &&
-            (wparam == HTMINBUTTON || wparam == HTMAXBUTTON || wparam == HTCLOSE))
-        {
-            TRACKMOUSEEVENT ev{};
-            ev.cbSize = sizeof(TRACKMOUSEEVENT);
-            // TME_NONCLIENT is absolutely critical here. In my experimentation,
-            // we'd get WM_MOUSELEAVE messages after just a HOVER_DEFAULT
-            // timeout even though we're not requesting TME_HOVER, which kinda
-            // ruined the whole point of this.
-            ev.dwFlags = TME_LEAVE | TME_NONCLIENT;
-            ev.hwndTrack = _dragBarWindow.get();
-            ev.dwHoverTime = HOVER_DEFAULT; // we don't _really_ care about this.
-            LOG_IF_WIN32_BOOL_FALSE(TrackMouseEvent(&ev));
-            _trackingMouse = true;
-        }
-        break;
+            //     // [[fallthrough]]
+            // }
+            // case HTMINBUTTON:
+            // case HTCLOSE:
+            //     _titlebar.HoverButton(static_cast<winrt::TerminalApp::CaptionButton>(wparam));
+            //     break;
+            // default:
+            //     _titlebar.ReleaseButtons();
+            // }
 
-    case WM_NCMOUSELEAVE:
-    case WM_MOUSELEAVE:
-        // When the mouse leaves the drag rect, make sure to dismiss any hover.
-        _titlebar.ReleaseButtons();
-        _trackingMouse = false;
-        break;
+            // // If we haven't previously asked for mouse tracking, request mouse
+            // // tracking. We need to do this so we can get the WM_NCMOUSELEAVE
+            // // message when the mouse leave the titlebar. Otherwise, we won't always
+            // // get that message (especially if the user moves the mouse _real
+            // // fast_).
+            // if (!_trackingMouse &&
+            //     (wparam == HTMINBUTTON || wparam == HTMAXBUTTON || wparam == HTCLOSE))
+            // {
+            //     TRACKMOUSEEVENT ev{};
+            //     ev.cbSize = sizeof(TRACKMOUSEEVENT);
+            //     // TME_NONCLIENT is absolutely critical here. In my experimentation,
+            //     // we'd get WM_MOUSELEAVE messages after just a HOVER_DEFAULT
+            //     // timeout even though we're not requesting TME_HOVER, which kinda
+            //     // ruined the whole point of this.
+            //     ev.dwFlags = TME_LEAVE | TME_NONCLIENT;
+            //     ev.hwndTrack = _dragBarWindow.get();
+            //     ev.dwHoverTime = HOVER_DEFAULT; // we don't _really_ care about this.
+            //     LOG_IF_WIN32_BOOL_FALSE(TrackMouseEvent(&ev));
+            //     _trackingMouse = true;
+            // }
+            // break;
+        }
+    // case WM_NCMOUSELEAVE:
+    // case WM_MOUSELEAVE:
+    //     // When the mouse leaves the drag rect, make sure to dismiss any hover.
+    //     _titlebar.ReleaseButtons();
+    //     _trackingMouse = false;
+    //     break;
 
     // NB: *Shouldn't be forwarding these* when they're not over the caption
     // because they can inadvertently take action using the system's default
@@ -238,44 +287,45 @@ LRESULT NonClientIslandWindow::_InputSinkMessageHandler(UINT const message,
             auto parentWindow{ GetHandle() };
             return SendMessage(parentWindow, message, wparam, lparam);
         }
-        // The buttons won't work as you'd expect; we need to handle those
-        // ourselves.
-        case HTMINBUTTON:
-        case HTMAXBUTTON:
-        case HTCLOSE:
-            _titlebar.PressButton(static_cast<winrt::TerminalApp::CaptionButton>(wparam));
-            break;
-        }
-        return 0;
+            // // The buttons won't work as you'd expect; we need to handle those
+            // // ourselves.
+            // case HTMINBUTTON:
+            // case HTMAXBUTTON:
+            // case HTCLOSE:
+            //     _titlebar.PressButton(static_cast<winrt::TerminalApp::CaptionButton>(wparam));
+            //     break;
+            // }
+            // return 0;
 
-    case WM_NCLBUTTONUP:
-        // Manual handling for mouse RELEASES in the drag bar. If it's in a
-        // caption button, then manually handle what we'd expect for that button.
-        //
-        // If it's not in a caption button, then just forward the message along
-        // to the root HWND.
-        switch (wparam)
-        {
-        case HTTOP:
-        case HTCAPTION:
-        {
-            // Pass caption-related nonclient messages to the parent window.
-            // The buttons won't work as you'd expect; we need to handle those ourselves.
-            auto parentWindow{ GetHandle() };
-            return SendMessage(parentWindow, message, wparam, lparam);
-        }
-        break;
-
-        // If we do find a button, then tell the titlebar to raise the same
-        // event that would be raised if it were "tapped"
-        case HTMINBUTTON:
-        case HTMAXBUTTON:
-        case HTCLOSE:
-            _titlebar.ReleaseButtons();
-            _titlebar.ClickButton(static_cast<winrt::TerminalApp::CaptionButton>(wparam));
+        case WM_NCLBUTTONUP:
+            // Manual handling for mouse RELEASES in the drag bar. If it's in a
+            // caption button, then manually handle what we'd expect for that button.
+            //
+            // If it's not in a caption button, then just forward the message along
+            // to the root HWND.
+            switch (wparam)
+            {
+            case HTTOP:
+            case HTCAPTION:
+            {
+                // Pass caption-related nonclient messages to the parent window.
+                // The buttons won't work as you'd expect; we need to handle those ourselves.
+                auto parentWindow{ GetHandle() };
+                return SendMessage(parentWindow, message, wparam, lparam);
+            }
             break;
+
+                // // If we do find a button, then tell the titlebar to raise the same
+                // // event that would be raised if it were "tapped"
+                // case HTMINBUTTON:
+                // case HTMAXBUTTON:
+                // case HTCLOSE:
+                //     _titlebar.ReleaseButtons();
+                //     _titlebar.ClickButton(static_cast<winrt::TerminalApp::CaptionButton>(wparam));
+                //     break;
+            }
+            return 0;
         }
-        return 0;
 
     // Make sure to pass along right-clicks in this region to our parent window
     // - we don't need to handle these.
@@ -506,8 +556,8 @@ void NonClientIslandWindow::_OnMaximizeChange() noexcept
         const auto isIconified = WI_IsFlagSet(windowStyle, WS_ICONIC);
 
         const auto state = _isMaximized ? winrt::TerminalApp::WindowVisualState::WindowVisualStateMaximized :
-                           isIconified  ? winrt::TerminalApp::WindowVisualState::WindowVisualStateIconified :
-                                          winrt::TerminalApp::WindowVisualState::WindowVisualStateNormal;
+                                          isIconified ? winrt::TerminalApp::WindowVisualState::WindowVisualStateIconified :
+                                                        winrt::TerminalApp::WindowVisualState::WindowVisualStateNormal;
 
         try
         {
@@ -860,7 +910,9 @@ void NonClientIslandWindow::_UpdateFrameMargins() const noexcept
     // We can't set it to all 0's unfortunately.
     if (_borderless)
     {
-        margins.cyTopHeight = 1;
+        // margins.cyTopHeight = 1;
+        // margins.cyTopHeight = static_cast<int>(_titlebar.ActualHeight());
+        margins.cyTopHeight = 40;
     }
     else if (_GetTopBorderHeight() != 0)
     {
@@ -885,6 +937,9 @@ void NonClientIslandWindow::_UpdateFrameMargins() const noexcept
         margins.cyTopHeight = -frame.top;
     }
 
+    // // For debugging: Manually set the top fram height to 16 px. Snap layouts only works in that space, apparently.
+    // margins.cyTopHeight = 16;
+
     // Extend the frame into the client area. microsoft/terminal#2735 - Just log
     // the failure here, don't crash. If DWM crashes for any reason, calling
     // THROW_IF_FAILED() will cause us to take a trip upstate. Just log, and
@@ -905,6 +960,7 @@ void NonClientIslandWindow::_UpdateFrameMargins() const noexcept
                                                             WPARAM const wParam,
                                                             LPARAM const lParam) noexcept
 {
+    // DwmDefWindowProc(GetHandle(), message, wParam, lParam, &lRet)
     switch (message)
     {
     case WM_SETCURSOR:
@@ -956,8 +1012,14 @@ void NonClientIslandWindow::_UpdateFrameMargins() const noexcept
         return 0;
     }
 
-    const auto topBorderHeight = _GetTopBorderHeight();
+    if (ps.rcPaint.left == ps.rcPaint.right && ps.rcPaint.top == ps.rcPaint.bottom)
+    {
+        return 0;
+    }
+    // TODO! NOTE: This seemingly does nothing anymore.
 
+    auto topBorderHeight = _GetTopBorderHeight();
+    topBorderHeight = 40;
     if (ps.rcPaint.top < topBorderHeight)
     {
         auto rcTopBorder = ps.rcPaint;
@@ -1130,3 +1192,8 @@ bool NonClientIslandWindow::_IsTitlebarVisible() const
 {
     return !(_fullscreen || _borderless);
 }
+
+void NonClientIslandWindow::SetTitlebarBackground(winrt::Windows::UI::Xaml::Media::Brush brush)
+{
+    _titlebar.Background(brush);
+}

src/cascadia/WindowsTerminal/NonClientIslandWindow.h

@@ -47,6 +47,8 @@ public:
     void SetTitlebarContent(winrt::Windows::UI::Xaml::UIElement content);
     void OnApplicationThemeChanged(const winrt::Windows::UI::Xaml::ElementTheme& requestedTheme) override;
 
+    void SetTitlebarBackground(winrt::Windows::UI::Xaml::Media::Brush brush);
+
 private:
     std::optional<COORD> _oldIslandPos;
 
@@ -65,7 +67,7 @@ private:
     bool _trackingMouse{ false };
 
     [[nodiscard]] static LRESULT __stdcall _StaticInputSinkWndProc(HWND const window, UINT const message, WPARAM const wparam, LPARAM const lparam) noexcept;
-    [[nodiscard]] LRESULT _InputSinkMessageHandler(UINT const message, WPARAM const wparam, LPARAM const lparam) noexcept;
+    [[nodiscard]] LRESULT _InputSinkMessageHandler(UINT const message, WPARAM const wparam, LPARAM lparam) noexcept;
 
     void _ResizeDragBarWindow() noexcept;
 

src/cascadia/WindowsTerminal/pch.h

@@ -64,7 +64,9 @@ Abstract:
 #include <winrt/Windows.UI.Core.h>
 #include <winrt/Windows.UI.Xaml.Controls.h>
 #include <winrt/Windows.UI.Xaml.Controls.Primitives.h>
+#include <winrt/Windows.ui.xaml.data.h>
 #include <winrt/Windows.ui.xaml.media.h>
+#include <winrt/Windows.ui.xaml.data.h>
 #include <winrt/Windows.ApplicationModel.h>
 #include <winrt/Windows.ApplicationModel.Resources.Core.h>
 #include <winrt/Windows.UI.Composition.h>

src/types/utils.cpp

@@ -87,31 +87,43 @@ std::string Utils::ColorToHexString(const til::color color)
 //      the correct format, throws E_INVALIDARG
 til::color Utils::ColorFromHexString(const std::string_view str)
 {
-    THROW_HR_IF(E_INVALIDARG, str.size() != 7 && str.size() != 4);
+    THROW_HR_IF(E_INVALIDARG, str.size() != 9 && str.size() != 7 && str.size() != 4);
     THROW_HR_IF(E_INVALIDARG, str.at(0) != '#');
 
     std::string rStr;
     std::string gStr;
     std::string bStr;
+    std::string aStr;
 
     if (str.size() == 4)
     {
         rStr = std::string(2, str.at(1));
         gStr = std::string(2, str.at(2));
         bStr = std::string(2, str.at(3));
+        aStr = "ff";
     }
-    else
+    else if (str.size() == 7)
     {
         rStr = std::string(&str.at(1), 2);
         gStr = std::string(&str.at(3), 2);
         bStr = std::string(&str.at(5), 2);
+        aStr = "ff";
+    }
+    else if (str.size() == 9)
+    {
+        // #aarrggbb
+        aStr = std::string(&str.at(1), 2);
+        rStr = std::string(&str.at(3), 2);
+        gStr = std::string(&str.at(5), 2);
+        bStr = std::string(&str.at(7), 2);
     }
 
     const auto r = gsl::narrow_cast<BYTE>(std::stoul(rStr, nullptr, 16));
     const auto g = gsl::narrow_cast<BYTE>(std::stoul(gStr, nullptr, 16));
     const auto b = gsl::narrow_cast<BYTE>(std::stoul(bStr, nullptr, 16));
+    const auto a = gsl::narrow_cast<BYTE>(std::stoul(aStr, nullptr, 16));
 
-    return til::color{ r, g, b };
+    return til::color{ r, g, b, a };
 }
 
 // Routine Description: