Bug 486556

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