SUMMARY On XORG, using a high dpi monitor (4k) and setting the scale to any value different than 100%, after changing some appearance option the dpi is reset to 100% for all new opened applications. Already open windows keep right scaling. STEPS TO REPRODUCE 1. Have a 4k monitor 2. Run a session using Xorg 3. Change the scaling to 200% 4. Log out and in to apply scalling 5. Open any window, it will appear with the right scaling 6. Open system settings 7. Change the color between of the predefined colors 8. Open any window and the dpi will appear as if it was set to 100% again OBSERVED RESULT After changing color settings, new windows appear with default 100% scaling even with scaling still registering on settings as 200%. EXPECTED RESULT After changing color settings, new windows should keep their defined scaling of 200%. SOFTWARE/OS VERSIONS Linux/KDE Plasma: Fedora Linux 36 (available in About System) KDE Plasma Version: 5.24.5 KDE Frameworks Version: 5.93.0 Qt Version: 5.15.3 ADDITIONAL INFORMATION Uploaded a video demonstrating the problem and my system information.
I uploaded a video showing the bug on youtube, to better explain the issue. https://youtu.be/z6IP20_oSRI
Created attachment 149529 [details] Youtube video showing the problem
That is exceptionally strange. Probably what happens is that changing the accent color signals some change that gets handled by something else which resets the internal DPI value or something. Cannot reproduce on Wayland or X11 FWIW.
Yes, as you said apparently some program as messing with the system scaling, I installed Kde Neon on my pen drive, run on my computer and the bug didn't happen, sorry for the non bug report.