SUMMARY Hi! I've fallen in love with the 'Wobbly Windows' effect. It transforms interactions with windows into something more connected with the user - instead of windows being simple rectangles that just immediately jump to wherever you want them to be, they become almost physical objects that you feel like you can touch. However, I've encountered a slight problem with it. Windows affected by this effect become blurry when I use fractional scaling (I typically use 125%, as anything lower is too small, and anything higher is too big). The end result is very similar to the blurry X11 windows seen when using `Legacy applications (X11): Scaled by the system`. However, this affects both Wayland and X11 apps, leading me to assume that the effect is applied before the window has a chance to be properly scaled. Consequently, the entire window is upscaled only after its geometry has been changed, resulting in blurriness. STEPS TO REPRODUCE 1. Enable the 'Wobbly Windows' effect in 'Window Management' -> 'Desktop Effects' -> 'Wobbly Windows' 2. Enable fractional scaling in 'Display & Monitor' -> 'Display Configuration' -> 'Scale' (use values like 125%, 150%, 175%, etc.) 3. Try to move any window to activate the effect. OBSERVED RESULT Whenever a window is moved (i.e., when the effect is applied to it), it becomes blurry. Which also happens even if you hold the window with your mouse perfectly still (so that its geometry doesn't change and it remains a plain old rectangle). EXPECTED RESULT A window should remain sharp and clear, just as it does when no scaling is applied. SOFTWARE/OS VERSIONS KDE Plasma Version: 6.0.4 KDE Frameworks Version: 6.1.0 Qt Version: 6.7.0 Kernel Version: 6.8.7-300.fc40.x86_64 (64-bit) Graphics Platform: Wayland ADDITIONAL INFORMATION This bug report appears to be an almost exact duplicate of 461283, which was presumably fixed by https://invent.kde.org/plasma/kwin/-/commit/19970bd63981504bad7fde626644f487b9cf7abc. However, it seems that some users experienced this problem even without scaling being applied, which is not the case for me - at 100%, windows remain perfectly crisp as they should. So, I believe this issue is different (especially considering the fact that I still can observe it after it's been fixed) and it somehow stems from the fact that I use fractional scaling.
I was able to reproduce Bug 461283 in the past, but now I can't anymore with current git master. At any scale factor between 125% and 225%, there's no blurriness while dragging anymore. So I suspect a further fix went in that's only in Plasma 6.1 (which I'm using, but you're not, and this appears to be the only significant software difference between our systems, as I'm using Fedora 40 as well). Do feel free to re-open this if you still encounter it in Plasma 6.1, though. In that case perhaps there are differences in graphics hardware or drivers that could explain it. I'm using an Intel HD620 iGPU.
Thanks a lot for the swift response! I thought that if any work had been done for the silly little things like wobbly windows, it would be more likely during the transition from Plasma 5 to Plasma 6. So, when I saw that the effect still produces blurriness after the update, I didn't expect that somebody had already fixed it in the upcoming 6.1 and thus decided to create this bug report. Anyways, gonna impatiently wait for 6.1 for this and many other reasons then :)