Bug 379027

Summary: can’t resize or move windows, copy&paste does not work
Product: [Plasma] kwin Reporter: Albert Zeyer <albzey>
Component: generalAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED UNMAINTAINED    
Severity: major    
Priority: NOR    
Version First Reported In: unspecified   
Target Milestone: ---   
Platform: Ubuntu   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description Albert Zeyer 2017-04-21 07:46:52 UTC 
Ubuntu 16.04, KDE 5.5.5.

You cannot move windows around nor resize them. Changing the focus and setting one windows to the front still works.

Also copy&paste does not work anymore.

This condition sometimes happens (maybe once in a month or so).

This very much describes the problem and provides a working solution for me:
http://lemire.me/blog/2005/09/28/strange-kde-bug-cant-resize-or-move-windows/windows

Note that the report is from 2005! And still people commenting on it (2017) that this works for them.

Basically, what (temporarily) solved the problem for me was:

killall kwin_x11
kwrapper5 kwin_x11 --replace
Comment 1 Martin Flöser 2017-04-21 13:15:35 UTC 
I'm sorry but version 5.5 is no longer supported and we don't investigate bugs in it. If you need user support please ask at forum.kde.org