STEPS TO REPRODUCE 1. open a video - I use Haruna player 2. open another app 3. alt+tab to video player and hold alt key OBSERVED RESULT the video is extremely laggy while we hold alt key EXPECTED RESULT the video plays with normal framerate SOFTWARE/OS VERSIONS Operating System: Arch Linux KDE Plasma Version: 6.3.90 KDE Frameworks Version: 6.14.0 Qt Version: 6.9.0 Kernel Version: 6.14.6-arch1-1 (64-bit) Graphics Platform: Wayland Processors: 8 × Intel® Core™ i7-4790 CPU @ 3.60GHz Memory: 32 GiB of RAM (31,2 GiB usable) Graphics Processor: Intel® HD Graphics 4600
Is this a regression in comparison to 6.3?
Yes.
FWIW I cannot reproduce the issue on my machine. It might a graphics driver or some frame scheduling issue (or maybe the gpu is not keeping up with blur or something).
Did you enable color management or something?
I also cannot reproduce this. My hardware is substantially newer though: Processors: 16 × AMD Ryzen 7 7840U w/ Radeon™ 780M Graphics Memory: 16 GiB of RAM (14.9 GiB usable) Graphics Processor: AMD Radeon 780M It could be something that only shows up on older hardware. One thing to mention... when you hold the Alt key, the selection highlight effect should go all the way to to the end of the window list/grid, but not loop around. That's the behavior you see, right? And if so, does the lag happen only while the highlight is moving, or does it persist after the highlight reaches the end and stops?
I use an icc color profile. The bug only occurs if "Color accuracy" is set to "Prefer color accuracy" in Display Configuration KCM.
In that case this may be at least somewhat expected. The UI for that feature does warn you that it will reduce performance.
Older hardware like that is especially affected by the increased bit depth, this is indeed expected. The option is set to prefer efficiency for a reason.