Bug 394246

Summary: kwin ignores _NET_WM_FULLSCREEN_MONITORS
Product: [Plasma] kwin Reporter: Pierre Ossman <ossman>
Component: multi-screenAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED DUPLICATE    
Severity: normal    
Priority: NOR    
Version: 5.12.4   
Target Milestone: ---   
Platform: Other   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description Pierre Ossman 2018-05-14 10:55:41 UTC 
KWin currently ignores the _NET_WM_FULLSCREEN_MONITORS property on windows. This property is used to control over which monitors an applications wants to be displayed. Generally this contains either a single monitor, or all of them.

KWin claims to support this feature though as it has _NET_WM_FULLSCREEN_MONITORS in _NET_SUPPORTED.

Tested on Fedora 27, but we've gotten reports from other distributions as well. Our bug entry:

https://www.cendio.com/bugzilla/show_bug.cgi?id=5482

There is a "Video Wall" script that sort-of works as a workaround. However it also ignores _NET_WM_FULLSCREEN_MONITORS and just assumes all monitors should be used, ignoring the application's settings.
Comment 1 Martin Flöser 2018-05-14 14:49:30 UTC 
What frameworks version are you using
Comment 2 Pierre Ossman 2018-05-14 14:53:14 UTC 
5.44.0-2.fc27
Comment 3 Martin Flöser 2018-05-14 15:53:18 UTC 
Please tell your distribution to ship bug fixes in a timely manner.

*** This bug has been marked as a duplicate of bug 391960 ***
Comment 4 Pierre Ossman 2018-05-15 07:30:59 UTC 
Hmm... Just to make sure I'm not misunderstanding things. The patch on bug 391960 looks like it is touching client code? I'm seeing this problem with non-KDE applications. They're not even using Qt.
Comment 5 Martin Flöser 2018-05-15 15:41:23 UTC 
You are misunderstanding. Just because it says client doesn't mean it's code running in clients. Trust me, an update will fix it.
Comment 6 Pierre Ossman 2018-05-16 07:14:47 UTC 
Awesome. Will wait until I get my hands on an updated system and retest.