Bug 430573

Summary: Plasma on Wayland crashes when dragging an application out of the menu
Product: [Plasma] kwin Reporter: Firlaev-Hans <firlaevhanskde.upstream314>
Component: generalAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED FIXED    
Severity: crash CC: nate, plasma-bugs-null
Priority: NOR Keywords: wayland-only
Version First Reported In: 5.20.4Flags: firlaevhanskde.upstream314: Wayland+
Target Milestone: ---   
Platform: Manjaro   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description Firlaev-Hans 2020-12-19 11:22:44 UTC 
When I tried to drag an application from the application menu or from KRunner into Latte-Dock, the screen froze as soon as the mouse cursor left the menu, then I got back to SDDM.

STEPS TO REPRODUCE
1. Start Plasma on Wayland
2. Open the application menu or Krunner
3. Try to drag the application out of the menu

OBSERVED RESULT
The Plasma Wayland session crashes. On X11, it does not.

EXPECTED RESULT
Applications can be dragged from the menu to the likes of Latte Dock etc.

SOFTWARE/OS VERSIONS
OS: Manjaro 
KDE Plasma Version: 5.20.4 
KDE Frameworks Version: 5.76.0
Qt Version: 5.15.2
Comment 2 Firlaev-Hans 2020-12-19 19:53:07 UTC 
(In reply to Nate Graham from comment #1)
> Can you add a backtrace? See
> https://community.kde.org/Guidelines_and_HOWTOs/Debugging/
> How_to_create_useful_crash_reports#Retrieving_a_backtrace_using_coredumpctl

Looks like it is kwin_wayland, not plasmashell that crashed. Whoops. Also, the same crash can happen when dragging around items in the dock.
Unfortunately the coredump for kwin_wayland is "truncated" so I'm afraid this might not be very useful:

#0  0x00007ff96a2162b8 in ?? ()
Backtrace stopped: Cannot access memory at address 0x7ffe871b54c0
Comment 3 Firlaev-Hans 2020-12-20 16:58:54 UTC 
I tried the latest KDE Neon Unstable in a VM and didn't run into this issue on Wayland.