Created attachment 185315 [details]
powertop showing plasmashell waking up CPU 63 times per second, roughly matching 60Hz screen refresh rate.

SUMMARY
The plasmashell repaints screen at every monitor frame, even when nothing on screen is changing. Until I interact with the System Tray Show Hidden Icons button by expanding the panel and collapsing. Then it behaves normally. It causes abnormally high power consumption on laptops, affecting battery life significantly.

STEPS TO REPRODUCE
1. Log in to plasma desktop normally
2. Run powertop, observe plasmashell waking up CPU at the frequency of screen refresh rate (i.e. 60, 75, 120).
3. Click "Show Hidden Icons" in system tray, expanding the hidden icons panel, then close the panel.
4. Run powertop again, observe that no plasmashell waking CPU up anymore.

OBSERVED RESULT
Right after logging in without clicking the "Show Hidden Icons", plasmashell will generate repaint event every frame, regardless if there is any change on screen.

EXPECTED RESULT
plasmashell should not generate constant repaint event, if there is no change on screen.

SOFTWARE/OS VERSIONS
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: Fedora Linux 42 KDE Plasma Desktop Edition
KDE Plasma Version: 6.4.5
KDE Frameworks Version: 6.18.0
Qt Version: 6.9.2

ADDITIONAL INFORMATION