Absolutely everything is awful and I have no idea how to fix this. Better just not then I guess

Manually picking a tab color doesn't seem to work right, so let's sort that out.

  But otherwise the selected / deselected tab colors seem right. It was the `SelectedBackgroundPath.Fill` that was basically totally overriding the background color.

  No idea where to go next with the manual color overrides. Maybe I missed something. Probably did.

build/packages.config

@@ -4,7 +4,8 @@
   <package id="Microsoft.Taef" version="10.60.210621002" targetFramework="native" />
   <package id="Microsoft.Internal.PGO-Helpers.Cpp" version="0.2.34" targetFramework="native" />
   <!-- This cannot be included in another project that depends on XAML (as it would be a duplicate package ID) -->
-  <package id="Microsoft.UI.Xaml" version="2.7.3" targetFramework="native" />
+  <package id="Microsoft.UI.Xaml" version="2.8.2" targetFramework="native" />
+  <package id="Microsoft.Web.WebView2" version="1.0.1587.40" targetFramework="native" />
   <package id="Microsoft.Debugging.Tools.PdbStr" version="20220617.1556.0" targetFramework="native" />
   <package id="Microsoft.Debugging.Tools.SrcTool" version="20220617.1556.0" targetFramework="native" />
 </packages>

common.openconsole.props

@@ -18,14 +18,14 @@
 
     This version should be tracked in all project packages.config files for projects that depend on Xaml.
     -->
-    <TerminalMUXVersion>2.7.3-prerelease.220816001</TerminalMUXVersion>
+    <TerminalMUXVersion>2.8.2-prerelease.220830001</TerminalMUXVersion>
     <!--
     For the Windows 11-specific build, we're targeting the public version of Microsoft.UI.Xaml.
     This version emits a package dependency instead of embedding the dependency in our own package.
 
     This version should be tracked in build/packages.config.
     -->
-    <TerminalMUXVersion Condition="'$(TerminalTargetWindowsVersion)'=='Win11'">2.7.3</TerminalMUXVersion>
+    <TerminalMUXVersion Condition="'$(TerminalTargetWindowsVersion)'=='Win11'">2.8.2</TerminalMUXVersion>
   </PropertyGroup>
 
 </Project>

src/cascadia/TerminalApp/TabBase.cpp

@@ -462,8 +462,46 @@ namespace winrt::TerminalApp::implementation
         // In GH#11294 we thought we'd still need to set
         // TabViewItemHeaderBackground manually, but GH#11382 discovered that
         // Background() was actually okay after all.
-        TabViewItem().Background(deselectedTabBrush);
-        TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderBackgroundSelected"), selectedTabBrush);
+        // TabViewItem().Background(deselectedTabBrush);
+        // TabViewItem().Background(selectedTabBrush); // This does seem to colorize the selected tab correctly, but not the deselected one
+        // TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderBackground"), deselectedTabBrush);
+        // TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderBackgroundSelected"), selectedTabBrush);
+
+        // {
+        //     // Attempt 1
+        //     TabViewItem().Background(selectedTabBrush); // This does seem to colorize the selected tab correctly, but not the deselected one
+        //     TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderBackground"), deselectedTabBrush);
+        //     TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderBackgroundSelected"), selectedTabBrush);
+        //     // This sorta worked, but deselected tabs were broken.
+        //     // Everything was the selected tab color. yikes.
+        // }
+        // {
+        //     // Attempt 2
+        //     TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderBackground"), deselectedTabBrush);
+        //     TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderBackgroundSelected"), selectedTabBrush);
+        //     // This didn't work at all. Deslected tabs and selected ones were not colorized.
+        //     // * Selected were that default blackish color
+        //     // * Deselected were transparent
+        // }
+
+        // {
+        //     // Attempt 3
+        //     TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderBackground"), deselectedTabBrush);
+        //     TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderBackgroundSelected"), selectedTabBrush);
+        //     // Additionally,
+        //     // <Setter Target="TabContainer.Background" Value="{ThemeResource TabViewItemHeaderBackgroundSelected}" />
+        //     // in <VisualState x:Name="Selected">.Setters
+        // }
+
+        {
+            // Attempt 4
+            // TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderBackground"), deselectedTabBrush);
+            TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderBackgroundSelected"), selectedTabBrush);
+
+            TabViewItem().Background(deselectedTabBrush);
+            // Additionally, changes to the XAML
+        }
+
         TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderBackgroundPointerOver"), hoverTabBrush);
         TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderBackgroundPressed"), selectedTabBrush);
 
@@ -471,7 +509,7 @@ namespace winrt::TerminalApp::implementation
         // when the TabViewItem isn't selected, but not when it is hovered,
         // pressed, dragged, or selected, so we'll need to just set them all
         // anyways.
-        TabViewItem().Foreground(deselectedFontBrush);
+        // TabViewItem().Foreground(deselectedFontBrush); // TODO!
         TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderForeground"), deselectedFontBrush);
         TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderForegroundSelected"), fontBrush);
         TabViewItem().Resources().Insert(winrt::box_value(L"TabViewItemHeaderForegroundPointerOver"), fontBrush);
@@ -537,7 +575,7 @@ namespace winrt::TerminalApp::implementation
         // GH#11382 DON'T set the background to null. If you do that, then the
         // tab won't be hit testable at all. Transparent, however, is a totally
         // valid hit test target. That makes sense.
-        TabViewItem().Background(WUX::Media::SolidColorBrush{ Windows::UI::Colors::Transparent() });
+        // TabViewItem().Background(WUX::Media::SolidColorBrush{ Windows::UI::Colors::Transparent() });
 
         _RefreshVisualState();
     }

src/cascadia/TerminalApp/TabRowControl.xaml

@@ -14,6 +14,15 @@
 
     <!--  GH#13143: Make sure that the Background is actually TabViewBackground here, not Transparent. This is load bearing, for showTabsInTitlebar=false.  -->
 
+
+    <ContentPresenter.Resources>
+        <ResourceDictionary>
+            <ResourceDictionary.MergedDictionaries>
+                <ResourceDictionary Source="TabViewStyles.xaml" />
+            </ResourceDictionary.MergedDictionaries>
+        </ResourceDictionary>
+    </ContentPresenter.Resources>
+
     <mux:TabView x:Name="TabView"
                  VerticalAlignment="Bottom"
                  HorizontalContentAlignment="Stretch"
@@ -22,6 +31,7 @@
                  CanDragTabs="True"
                  CanReorderTabs="True"
                  IsAddTabButtonVisible="false"
+                 Style="{StaticResource MyTabViewStyle}"
                  TabWidthMode="Equal">
 
         <mux:TabView.TabStripHeader>

src/cascadia/TerminalApp/TerminalAppLib.vcxproj

@@ -60,6 +60,9 @@
     <Page Include="CommandPalette.xaml">
       <SubType>Designer</SubType>
     </Page>
+    <Page Include="TabViewStyles.xaml">
+      <SubType>Designer</SubType>
+    </Page>
   </ItemGroup>
   <!-- ========================= Headers ======================== -->
   <ItemGroup>

src/cascadia/TerminalApp/packages.config

@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="Microsoft.UI.Xaml" version="2.7.3-prerelease.220816001" targetFramework="native" />
+  <package id="Microsoft.UI.Xaml" version="2.8.2-prerelease.220830001" targetFramework="native" />
 </packages>

src/cascadia/WindowsTerminal/WindowsTerminal.vcxproj

@@ -27,6 +27,14 @@
   <Import Project="$(OpenConsoleDir)src\common.nugetversions.props" />
   <Import Project="$(OpenConsoleDir)src\cppwinrt.build.pre.props" />
 
+  <PropertyGroup>
+    <!-- This magic property will let WebVeiw2 know that it needs to reveal its
+    winmd to us. Without it, the WebView2 targets don't think we're a WinRT
+    context, and our build will fail when MUX fails midl compile (due to missing
+    webview components). -->
+    <WebView2UseWinRT>true</WebView2UseWinRT>
+  </PropertyGroup>
+
   <ItemDefinitionGroup>
     <ClCompile>
       <SDLCheck>true</SDLCheck>

src/common.nugetversions.targets

@@ -54,6 +54,7 @@
 
     <!-- WinUI (which depends on WebView2 as of 2.8.0) -->
     <Import Project="$(MSBuildThisFileDirectory)..\packages\Microsoft.UI.Xaml.$(TerminalMUXVersion)\build\native\Microsoft.UI.Xaml.targets" Condition="'$(TerminalMUX)' == 'true' and Exists('$(MSBuildThisFileDirectory)..\packages\Microsoft.UI.Xaml.$(TerminalMUXVersion)\build\native\Microsoft.UI.Xaml.targets')" />
+    <Import Project="$(MSBuildThisFileDirectory)..\packages\Microsoft.Web.WebView2.1.0.1587.40\build\native\Microsoft.Web.WebView2.targets" Condition="'$(TerminalMUX)' == 'true' and Exists('$(MSBuildThisFileDirectory)..\packages\Microsoft.Web.WebView2.1.0.1587.40\build\native\Microsoft.Web.WebView2.targets')" />
 
     <!-- WIL (so widely used that this one does not have a TerminalWIL opt-in property; it is automatic) -->
     <Import Project="$(MSBuildThisFileDirectory)..\packages\Microsoft.Windows.ImplementationLibrary.1.0.220201.1\build\native\Microsoft.Windows.ImplementationLibrary.targets" Condition="Exists('$(MSBuildThisFileDirectory)..\packages\Microsoft.Windows.ImplementationLibrary.1.0.220201.1\build\native\Microsoft.Windows.ImplementationLibrary.targets')" />
@@ -87,6 +88,7 @@
 
     <!-- WinUI (which depends on WebView2 as of 2.8.0) -->
     <Error Condition="'$(TerminalMUX)' == 'true' AND !Exists('$(MSBuildThisFileDirectory)..\packages\Microsoft.UI.Xaml.$(TerminalMUXVersion)\build\native\Microsoft.UI.Xaml.targets')" Text="$([System.String]::Format('$(ErrorText)', '$(MSBuildThisFileDirectory)..\packages\Microsoft.UI.Xaml.$(TerminalMUXVersion)\build\native\Microsoft.UI.Xaml.targets'))" />
+    <Error Condition="'$(TerminalMUX)' == 'true' AND !Exists('$(MSBuildThisFileDirectory)..\packages\Microsoft.Web.WebView2.1.0.1587.40\build\native\Microsoft.Web.WebView2.targets')" Text="$([System.String]::Format('$(ErrorText)', '$(MSBuildThisFileDirectory)..\packages\Microsoft.Web.WebView2.1.0.1587.40\build\native\Microsoft.Web.WebView2.targets'))" />
 
     <!-- WIL (so widely used that this one does not have a TerminalWIL opt-in property; it is automatic) -->
     <Error Condition="!Exists('$(MSBuildThisFileDirectory)..\packages\Microsoft.Windows.ImplementationLibrary.1.0.220201.1\build\native\Microsoft.Windows.ImplementationLibrary.targets')" Text="$([System.String]::Format('$(ErrorText)', '$(MSBuildThisFileDirectory)..\packages\Microsoft.Windows.ImplementationLibrary.1.0.220201.1\build\native\Microsoft.Windows.ImplementationLibrary.targets'))" />