Bug 486556

Summary: No longer possible to disable composition through the API
Product: [Plasma] kwin Reporter: Alberto Salvia Novella <es20490446e>
Component: compositingAssignee: KWin default assignee <kwin-bugs-null>
Status: CONFIRMED ---    
Severity: normal CC: nate
Priority: NOR Keywords: regression
Version: 6.0.4   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description Alberto Salvia Novella 2024-05-04 09:45:56 UTC
Kwin_X11 used to have three methods for disable composition:

1. By creating a window that had the hint: _NET_WM_BYPASS_COMPOSITOR
2. By running the command: qdbus org.kde.KWin /Compositor suspend
3. From QML, by calling: client.blocksCompositing = true

The two last methods have been removed. This renders one of the most popular Kwin scripts broken, Autocomposer (https://www.opendesktop.org/p/1502826).

This script is important for people because it allows running games fluently, more in low end hardware. Without it games perform slower, specially if desktop effects like "Blur" or "Background Contrast" are in use.

The only way to fix Autocomposer right now is by creating an invisible window that holds the first hint, which is ugly.

Alternatively the option "allow applications to block compositing" could affect full-screen applications that don't explicitly set the hint, as Autocomposer does. This is a more expected behavior.