Bug 405982

Summary: Crash when using grouped window list
Product: [Plasma] plasmashell Reporter: Dominik <dominikns>
Component: Window List widgetAssignee: Plasma Bugs List <plasma-bugs-null>
Status: RESOLVED WORKSFORME    
Severity: crash    
Priority: NOR    
Version First Reported In: 5.15.3   
Target Milestone: 1.0   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: two sample outputs of plasmashell and a screenshot

Description Dominik 2019-03-29 09:39:51 UTC
Created attachment 119111 [details]
two sample outputs of plasmashell and a screenshot

I use a separate control bar on the top of my screen which shows a list of opened programs (only the ones of the current workspace). Window grouping is enabled (e.g. two kwrite instances are shown as a single button). When I hover the mouse cursor over a task bar button I get a preview/thumbnail of the program's window. I regularly - but nor always - get an empty preview when the mouse cursor is placed over a grouped button (see attached screenshot). Clicking on this empty preview window segfaults plasmashell. It seems that plasmashell also segfaults if the mouse cursor hovers long enough over the button or the empty preview.


STEPS TO REPRODUCE
1. Create a new control bar
2. Add a window bar
3. Make sure grouping is enabled in window bar
4. Open two instances of the same program (e.g., open two files with kwrite)
5. Hover the mouse over the task bar entry of the program group (e.g., kwrite)
6. If bug happens: No window preview is shown, just a small (in vertical dimension) empty window
7. Hover the mouse over this window for some time or click on it
8. crash

OBSERVED RESULT
Segmentation fault ("Speicherzugriffsfehler") os plasmashell

EXPECTED RESULT
Preview window of the grouped windows

SOFTWARE/OS VERSIONS
Linux: Antergos (kernel: 5.0.4-arch1-1-ARCH)
KDE Plasma Version: 5.15.3
KDE Frameworks Version: 5.56
Qt Version: 5.12.2
Comment 1 Christoph Feck 2019-04-19 12:23:31 UTC
Please add the backtrace for the crash. For more information, please see https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports
Comment 2 Bug Janitor Service 2019-05-04 04:33:09 UTC
Dear Bug Submitter,

This bug has been in NEEDSINFO status with no change for at least
15 days. Please provide the requested information as soon as
possible and set the bug status as REPORTED. Due to regular bug
tracker maintenance, if the bug is still in NEEDSINFO status with
no change in 30 days the bug will be closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

If you have already provided the requested information, please
mark the bug as REPORTED so that the KDE team knows that the bug is
ready to be confirmed.

Thank you for helping us make KDE software even better for everyone!
Comment 3 Bug Janitor Service 2019-05-19 04:33:09 UTC
This bug has been in NEEDSINFO status with no change for at least
30 days. The bug is now closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

Thank you for helping us make KDE software even better for everyone!