Sudden flickering in all themes (video included)

Describe the bug
After first working flawlessly I am now experiencing slight flickering. Even a reinstall doesn't fix this issue. I tried several themes and it seems like this could be caused by multiple themes being on top of each other? I mainly use the cyberpunk theme but when I switch back to the default theme I can still see the Cyberpunk theme in the background slightly.

To Reproduce
Steps to reproduce the behavior:
Use the configuration tool
Save and apply the theme
Theme is loaded onto the display and the flickering immediately appears.

Environment:

• Smart screen model [ XuanFang 3.5”]
• Revision of this project [3.9.1]
• OS with version [Win11 23h2]
• Python version [no clue?]
• Hardware [AMD Ryzen 7800X3D, NVIDIA RTX5080]

Additional context
As mentioned above it worked well for a couple of days and today I noticed this issue for the first time.

Video here:
https://www.youtube.com/shorts/u64k846XuiA (flickering and cyberpunk overlay present int he background)
https://www.youtube.com/shorts/SS-1J1d8cgM (well, i can see the flickering in the video on my phone however in the YT clip it's no longer noticable :| )

Start with the configuration tool and reproduce the issue on the XuanFang 3.5-inch display using revision 3.9.1 on Windows 11. Trace what happens when switching from the Cyberpunk theme to the default theme; done means theme changes no longer leave a visible overlay or cause flickering, verified with the reported reproduction steps.