Add support for Windows 10 Dark Theme

[KyroOW]

Role

Just using it

Suggestion

Support Windows 10 Dark Theme: Currently, there is either "light" and "dark" color presets in the settings of MultiMC, and "System" doesn't follow the theme of Windows 10 if it's set to light or dark mode (it stays white even when Windows 10 is set to Dark Mode), so, when using the "System" preset, and if Windows 10 is in Dark Mode, MultiMC should also turn to dark mode. (would be great if the title bar could also be dark)

Benefit

Unless we switch manually between the light and dark presets in the settings, MultiMC should automatically switch by itself corresponding with the Windows 10 theme like other programs, almost all windows programs supports this today. (it is especially annoying for people like me who have a program that switches windows 10 theme between light and dark depending on the time of the day.)

This suggestion is unique

• [X] I have searched the issue tracker and did not find an issue describing my suggestion, especially not one that has been rejected.

[jamierocks]

It's likely the same situation as with macOS, just requiring MultiMC to be built with a newer version of Qt. That comes at the cost of supporting some operating systems though - so might not happen anytime soon.

[phit]

macOS actually has a built in system dark theme MultiMC will use when built with newer Qt, Windows doesn't have that. A dark theme matching the Windows "Vista" theme of Qt will need to be made.

https://bugreports.qt.io/browse/QTBUG-72028

actually once Qt is updated, there's now a way to query the mode and MultiMC could at least switch to the Dark Fusion theme when dark mode is detected https://codereview.qt-project.org/c/qt/qtbase/+/278442

[jamierocks]

Oh, I assumed that Windows must have a dark mode for this to be a bug report.

This is less connected to the macos than I thought then.

[kb-1000]

Windows does, but it's very inconsistently applied