terminal/doc/AddASetting.md

# Adding a Settings Property

1. Add to wincon.w
    * THIS IS NOT IN OPENCONSOLE. Make sure you update
      `.../console/published/wincon.w` in the OS repo when you submit the PR.
      The branch won't build without it.
    * For now, you can update winconp.h with your consumable changes.
    * Define registry name (ex: `CONSOLE_REGISTRY_CURSORCOLOR`)
    * Add the setting to `CONSOLE_STATE_INFO`.
    * Define the property key ID and the property key itself.
        - Yes, the large majority of the `DEFINE_PROPERTYKEY` defs are the same, it's only the last byte of the guid that changes.

2. Add matching fields to Settings.hpp
    - Add getters, setters, the whole drill.

3. Add to the propsheet
    - We need to add it to *reading and writing* the registry from the propsheet, and *reading* the link from the propsheet. Yes, that's weird, but the propsheet is smart enough to re-use ShortcutSerialization::s_SetLinkValues, but not smart enough to do the same with RegistrySerialization.
    - `src/propsheet/registry.cpp`
        -  `propsheet/registry.cpp@InitRegistryValues` should initialize the default value for the property.
        -  `propsheet/registry.cpp@GetRegistryValues` should make sure to read the property from the registry.

4. Add the field to the propslib registry map.

5. Add the value to `ShortcutSerialization.cpp`
    - Read the value in `ShortcutSerialization::s_PopulateV2Properties`
    - Write the value in `ShortcutSerialization::s_SetLinkValues`

6. Add the setting to `Menu::s_GetConsoleState`, and `Menu::s_PropertiesUpdate`
Now, your new setting should be stored just like all the other properties.

7. Update the feature test properties to get add the setting as well
    - `ft_uia/Common/NativeMethods.cs@WinConP`:
        - `Wtypes.PROPERTYKEY PKEY_Console_`.
        - `NT_CONSOLE_PROPS`.

8. Add the default value for the setting to `win32k-settings.man`
    - If the setting shouldn't default to 0 or `nullptr`, then you'll need to set the default value of the setting in `win32k-settings.man`.

9. Update `Settings::InitFromStateInfo` and `Settings::CreateConsoleStateInfo` to get/set the value in a CONSOLE_STATE_INFO appropriately.