| Summary: | Fullscreen animation effect flickers window when spammed | ||
|---|---|---|---|
| Product: | [Frameworks and Libraries] frameworks-kwidgetsaddons | Reporter: | Tech-Tac <im.tech.tac> |
| Component: | general | Assignee: | Christoph Feck <cfeck> |
| Status: | CLOSED FIXED | ||
| Severity: | normal | CC: | kdelibs-bugs-null, nate |
| Priority: | NOR | Keywords: | accessibility |
| Version First Reported In: | 6.14.0 | ||
| Target Milestone: | --- | ||
| Platform: | Other | ||
| OS: | Linux | ||
| Latest Commit: | https://invent.kde.org/frameworks/kwidgetsaddons/-/commit/65590720a5f9c208b1ae973d37018cf9af54da2f | Version Fixed/Implemented In: | 6.16 |
| Sentry Crash Report: | |||
| Attachments: | Repeated fullscreen window flickers | ||
We could probably prevent subsequent triggerings if the key is held down. This is probably going to be important for accessibility, to prevent seizure-inducing flickering. In the meantime, don't do that! 😆 Looking into it, the flicker is not caused by the KWin effect, but rather than fact that key repeat is enabled for this action. Since it's a per-app action, there's nothing we can do for 3rd-party apps like Firefox. However for our own apps, we can at least disable key repeat for it so you can't accidentally trigger this issue by holding down F11. The standard action lives in KWidgetsAddons; moving there and working on it. Any KDE apps that don't use the standard action should be ported to use it, so they get this fix automatically. I believe the effect itself can be fixed (or rewritten), because another effect (https://store.kde.org/p/2136283) provides similar functionality to Fullscreen and Maximize (notably without the cross-fading) and doesn't flicker (https://bugs.kde.org/show_bug.cgi?id=505482, https://bugs.kde.org/show_bug.cgi?id=505478) Also please don't remove spam fullscreening! It breaks consistency and fun for the sake of "rubber bumpers" akin to those in iPadOS! Hah, I see what you did there! But this is a somewhat different case since it's a functional thing that's on by default (hold down the F11 key) rather than a visual thing that's off by default. Also, the KWin effect doesn't matter; disabling the effect still causes flicker. Hence, the problem is not about the KWin effect but rather the fact that you can enter and exit fullscreen repeatedly by holding down F11. This serves no useful purpose at all. You seem to be talking about the rapid layout shifts resulting from repeatedly toggling fullscreen, and yeah this is reasonable to fix even if the user doesn't deliberately hold down a key, it may for instance get stuck. But this issue was about not the layout shifts, but rather that the entire windows disappears in conjugation to the animation. Which is fixed by disabling key repeat, and doing so fixes other even more important issues too. So that's the change that it makes sense to pursue. Fixed with https://invent.kde.org/frameworks/kwidgetsaddons/-/commit/65590720a5f9c208b1ae973d37018cf9af54da2f for Frameworks 6.16. The original bug is still present and is likely a flaw in either the effect itself or KWin. The bug fixed here albeit welcome, was not the intended fix for the described issue. Now that key repeat is disabled, why are you repeatedly and intentionally pressing F11 in Konsole to enter and exit full screen? What's the use case? None, just playing around. Fixing this issue is not really necessary but it does contribute to overall polish, and satisfies my inner perfectionist. Then it's not worth putting effort into. We've already made the visual glitch not triggerable by accident; all you have to do now is to not intentionally cause problems for yourself. If you'd like to satisfy your inner perfectionist, then you should feel free to work on fixing it yourself, of course. But no one else is under any obligation to do that for you. :) |
Created attachment 182188 [details] Repeated fullscreen window flickers SUMMARY When holding down the button to fullscreen any window with the Fullscreen window animation effect enabled, the window flickers or even straight up disappears for the duration the fullscreen action is repeated for, while the blur layer behind it (if present) stays visible. STEPS TO REPRODUCE 1. Enable Fullscreen effect in Desktop Effects 2. Open Firefox or Konsole and hold down f11 3. Observe OBSERVED RESULT Window flickers or disappears EXPECTED RESULT Stays visible SOFTWARE/OS VERSIONS Arch Linux with kernel 6.15.1 KDE Plasma Version: 6.3.5 KDE Frameworks Version: 6.14.0 Qt Version: 6.9.0 ADDITIONAL INFORMATION GPU: AMD Radeon HD 7560D Drivers: Mesa 25.1.3, kernel radeon driver