Unable to change to Dark Mode

[FeedTheChunk]

Has the bug or similar already been reported?
I was unable to find any similar issues

Describe the bug
Going to the preferences and changing the theme to Dark Mode / System the theme stays in Light mode.

Screenshots

Version and Installation Information

• Found in version #: V2.0.0
• New install from Flathub

OS & Desktop (please complete the following information):
OS: Kubuntu oracular 24.10 x86_64
Kernel: Linux 6.11.0-13-generic
Shell: bash 5.2.32
Display (LG ULTRAGEAR): 2560x1440 @ 144 Hz in 27" [Exter*
Display (LG ULTRAGEAR): 2560x1440 @ 144 Hz in 27" [Exter]
Display (LG ULTRAGEAR): 2560x1440 @ 144 Hz in 27" [Exter]
DE: KDE Plasma 6.1.5
CPU: 13th Gen Intel(R) Core(TM) i5-13600K (20) @ 5.10 GHz
GPU 1: NVIDIA GeForce RTX 4060
Memory: 18.36 GiB / 62.58 GiB (29%)

[technosf]

@FeedTheChunk - Do you have a dark theme installed? Tuner is using the desktop dark theme, and what I have found is that if no dark theme is installed, there is no dark theme for Tuner to apply.

Could you try in your desktop preferences set the desktop theme appearance to 'Dark', restart and see if Tuner now flips between light and dark. Then, if you're using light theme, change back to that and see if Tuner now can flip back and forth.

[FeedTheChunk]

I do. I use Breeze Dark.

[technosf]

Can you try installing adwaita/libadwaita, and choosing adwaita-dark temporarily?

[FeedTheChunk]

libadwaita 1.0 was already installed but the dark theme was not. I installed it and selected it, no change. I'll reboot the machine as soon as I can, probably 10-15 min from now and report back. Thanks

[FeedTheChunk]

No change. Could it be a flatpak permission issue? I did install it from flathub and not compile from source.

[xgrind]

The problem is in flatpak. When I use compiled tuner, the dark theme works, even if the system theme is not dark.
But it does not work when installed via flatpak.
The first 3 are from compiled tuner and the last 3 are in flatpak:

https://imgur.com/a/8Qs7In7