Enable macOS Darkmode support for non legacy builds

[ann0see]

Short description of changes
The .plist files contained an opt out for macOS dark mode. Since we compile with Qt 5.15 or later on non legacy builds, there is no need to disable Dark mode support.

CHANGELOG: Mac: Enable dark-mode support on non legacy builds

Does this change need documentation? What needs to be documented and how?

No. Maybe screenshots.

Status of this Pull Request

Ready for review

What is missing until this pull request can be merged?

Nothing

Checklist

• I've verified that this Pull Request follows the general code principles
• I tested my code and it does what I want
• My code follows the style guide
• I waited some time after this Pull Request was opened and all GitHub checks completed without errors.
• I've filled all the content above

[ann0see]

@pljones @hoffie I know you don't have a Mac, so also asking @emlynmac for a review here.

[hoffie]

As you say, no way to test that for me. :)

Will this change Jamulus' appearance based on system settings? If so, it might be better to do that as part of 3.10.0?
Or is this some kind of app-specific opt-in? Then 3.9.1 would probably also be ok?

Should get some review/feedback by other Mac users as you say.
The universal build PR also contained names of known Mac users you could ping.

[pljones]

What effect does it have on the mixer in Fancy skin?

[emlynmac]

@pljones @hoffie I know you don't have a Mac, so also asking @emlynmac for a review here.

Is there a build I can fire up for a quick test?

[ann0see]

Will this change Jamulus' appearance based on system settings?

Yes.

What effect does it have on the mixer in Fancy skin?

See the screenshot.

Is there a build I can fire up for a quick test?

Just try the non legacy Mac artifact

[pljones]

See the screenshot.

Oh, that is Fancy skin in dark mode? Right! What does non-Fancy look like, then? (Similar to the settings page, I presume.)

[ann0see]

It seems as if the server name is not inverted.

[pljones]

Mmm, yep, could do with a little more work. I think it's styled directly in the code.

It's also worth checking when connected to a server that's recording and when Mute Myself is enabled (and both).

[ann0see]

Pasting https://forum.qt.io/topic/103465/how-to-react-to-light-dark-mode-changes-in-macos/4 here. Debian 12 Qt6 seems to use the same values.

The stylesheet seems to be in clientdlg.cpp

Also: Qt6-wayland might need to be installed: https://unix.stackexchange.com/questions/598099/could-not-find-the-qt-platform-plugin-wayland

The return value of the palette().color call should be equal to QColor::fromRgbF(0.196078, 0.196078, 0.196078, 1);

[ann0see]

Ok. @pljones Implemented for Linux Gnome. I'll test it on macOS later.

[ann0see]

@pljones please merge this if you feel it's OK. last time I was able to test it on macOS everything was as in the screenshots above (especially the now merged PR which fixed the dark mode)

[pljones]

Are you saying the server name still displays in black on dark grey? If so, then it needs fixing still, yes?

[ann0see]

No. The now merged other PR fixed this issue.