SUMMARY On Wayland, performacne is not as good as on X11 in Plasma on my machine. I just tested with only one window open, Dolphin maximized with transparency and blur, performance is good on X11, while the FPS drop on Wayland. STEPS TO REPRODUCE 1. Use a transparent theme with blur enabled 2. Open Dolphin and maximize it so that the blur covers almost the whole screen. 3. Open the K menu and see sluggishness. OBSERVED RESULT EXPECTED RESULT Remain smooth like X11 ! SOFTWARE/OS VERSIONS Windows: macOS: Linux/KDE Plasma: (available in About System) KDE Plasma Version: 5.19.2 KDE Frameworks Version: 5.71 Qt Version: 5.15 ADDITIONAL INFORMATION Intel HD 620 graphics with Modesettings driver.
It seems to be the same bug as https://bugs.kde.org/show_bug.cgi?id=419760, though I'm not 100% sure.
I'm having the same issue KDE Plasma Version: 5.22.3 KDE Frameworks Version: 5.83.0 Qt Version: 5.15.2 Kernel Version: 5.12.14-zen1-1-zen (64-bit) Graphics Platform: Wayland Graphics Processor: Mesa DRI Intel® HD Graphics 4600
*** This bug has been marked as a duplicate of bug 419760 ***
Things are way better since Plasma 5.21, though !