STEPS TO REPRODUCE 1. Disable the minimize and/or open windows effect 2. Open a window OBSERVED RESULT The shadow will be displayed at kind of two different times, first it appears instantly, as it should be, but then a kind of effect is applied over it to make it stronger EXPECTED RESULT Since the effect is turned off then it doesn't make sense to have an animation in this scene. I would expect the window to simply appear and no effects to show. SOFTWARE/OS VERSIONS Operating System: Arch Linux KDE Plasma Version: 5.23.4 KDE Frameworks Version: 5.89.0 Qt Version: 5.15.2 Graphics Platform: X11 ADDITIONAL INFORMATION 1. It is possible to work around this by setting the speed of the animations to maximum, but with that the other effects will be lost. 2. Decreasing the size and strength of the shadow is also helpful, but it lowers the contrast between the focused window and the ones open in the background 3. I slowed down the animations while recording the video to make it sharper.
Created attachment 144624 [details] screen recorder
This bug was reported against an outdated version of KWin. We have made many changes since the. If the issue persists in newer versions can you reopen the bug report updating the version number.