Bug 428617

Summary: GTK+ settings crashes when applying
Product: [Applications] systemsettings Reporter: Sky Barnes <thea>
Component: kcm_styleAssignee: Plasma Bugs List <plasma-bugs-null>
Status: RESOLVED DOWNSTREAM    
Severity: normal CC: mail
Priority: NOR    
Version First Reported In: 5.19.5   
Target Milestone: ---   
Platform: Kubuntu   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description Sky Barnes 2020-11-02 21:53:46 UTC 
SUMMARY
When I change my GTK+ theme, clicking "Apply" applies the changes properly, but then immediately crashes System Settings.

STEPS TO REPRODUCE
1. Open System Settings
2. Change GTK+ theme
3. Click "Apply"

OBSERVED RESULT
GTK+ theme is changed, followed by a crash

EXPECTED RESULT
No crash afterwards

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Kubuntu 20.10
(available in About System)
KDE Plasma Version: 5.19.5
KDE Frameworks Version: 5.74.0
Qt Version: 5.14.2
Comment 1 Mikhail Zolotukhin 2020-11-02 22:24:33 UTC 
I cannot reproduce. Could you please provide a crash backtrace?
Comment 2 Mikhail Zolotukhin 2020-11-02 22:26:00 UTC 
And what GTK theme do you mean GTK2 or GTK3?
Comment 3 Sky Barnes 2020-11-02 22:32:25 UTC 
(In reply to Mikhail Zolotukhin from comment #1)
> I cannot reproduce. Could you please provide a crash backtrace?

What's the easiest way for me to get a stack trace of the crash?

(In reply to Mikhail Zolotukhin from comment #2)
> And what GTK theme do you mean GTK2 or GTK3?

Either one, just clicking Apply after a change is what crashes it.
Comment 4 Mikhail Zolotukhin 2020-11-02 23:02:39 UTC 
There should be a program called Dr Konqui or something like that on Kubuntu. It should show the notification after the crash happened and suggest you to show the backtrace if you click on it.
Comment 5 Sky Barnes 2020-11-02 23:16:48 UTC 
(In reply to Mikhail Zolotukhin from comment #4)
> There should be a program called Dr Konqui or something like that on
> Kubuntu. It should show the notification after the crash happened and
> suggest you to show the backtrace if you click on it.

Dr. Konqi doesn't show up when it crashes anymore, it did the first few times it happened, but now it just crashes silently. Is there another way to generate the backtrace?
Comment 7 Sky Barnes 2020-11-03 01:35:30 UTC 
(In reply to Christoph Feck from comment #6)
> Please see
> https://community.kde.org/Guidelines_and_HOWTOs/Debugging/
> How_to_create_useful_crash_reports#Retrieving_a_backtrace_with_GDB

So I did that, and it turns out the crash was in appmenu-gtk2 (a leftover package from before I switched to KDE); after removing that, the crash no longer occurs. Thanks for your help!
Comment 8 Christoph Feck 2020-11-03 20:32:55 UTC 
Thanks for the update; changing status.