Created attachment 149119 [details]
For some reason in the video the lag isn't so much noticeable.

SUMMARY
The prompt log out dialog (where you can also choose if you want to shutdown or restart your PC or just put it to sleep) is laggy when using KDE Plasma under Wayland.

STEPS TO REPRODUCE
1. Open "System Settings" and go to "Energy Saving".
2. In the "Button events handling" section go to "When power button pressed" and there choose "Prompt log out dialog".
3. Apply the changes and then use the power button to make the prompt log out dialog appear.
4. Use the cursor or the arrow keys to move across the buttons.

OBSERVED RESULT
The animations and the cursor are laggy.

EXPECTED RESULT
The animations are smooth and the cursor isn't laggy.

SOFTWARE/OS VERSIONS
Operating System: Arch Linux
KDE Plasma Version: 5.24.90
KDE Frameworks Version: 5.94.0
Qt Version: 5.15.4
Kernel Version: 5.17.9-arch1-1 (64-bit)
Graphics Platform: Wayland
Processors: 4 × Intel® Core™ i3-2350M CPU @ 2.30GHz
Memory: 7.7 GiB of RAM
Graphics Processor: Mesa Intel® HD Graphics 3000

ADDITIONAL INFORMATION
This didn't happen in KDE Plasma 5.24. The bug is only reproducible under Wayland.