[Bug]: Theme not detected on Linux AppImage

[Yiannis128]

Operating system

Linux

Version

0.7.7.1 (Official Build) (64-bit)

Have you tested that this is not an upstream issue or an issue with your configuration?

• I have tried reproducing this issue in Chrome and it could not be reproduced there
• I have tried reproducing this issue in ungoogled-chromium and it could not be reproduced there
• I have tried reproducing this issue in Helium with a new and empty profile using --user-data-dir command line argument and it could not be reproduced there

Description

The appearance of the browser is not applied when set to "device" properly, having the appearance set to "device" does not work.

How to Reproduce?

1. In the start page, click on the pencil "edit" icon.
2. In the sidebar, in the "Appearance" section, select "Device".
3. If you're on Light mode on the device it will not be applied despite other apps detecting and applying this properly.

Actual behavior

The light theme is not applied, you need to manually select "Light".

Expected behavior

The light theme should be applied when the system theme is set to light and vise versa for dark.

Additional context

OS: Linux 6.17.11-300.fc43.x86_64 Fedora running as AppImage.