Bug 503583

Summary: KHelpCenter's content area is transparent, and produces "ghost windows"
Product: [Applications] khelpcenter Reporter: Roke Julian Lockhart Beedell <4wy78uwh>
Component: generalAssignee: Documentation Editorial Team <kde-doc-english>
Status: RESOLVED UPSTREAM    
Severity: normal CC: john.kizer
Priority: NOR    
Version First Reported In: unspecified   
Target Milestone: ---   
Platform: Fedora RPMs   
OS: Linux   
URL: https://bugreports.qt.io/browse/QTBUG-135786
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: A Screencast Demonstrating The Problem
An "Active Window" Screenshot
A "Full Screen" Screenshot

Description Roke Julian Lockhart Beedell 2025-04-30 18:01:38 UTC 
Created attachment 180816 [details]
A Screencast Demonstrating The Problem

SUMMARY

KHelpCenter's QtWebEngine instance is transparent, and produces "ghost windows". [^1]

STEPS TO REPRODUCE

Merely invoke `khelpcenter`.

SOFTWARE/OS VERSIONS

I am using `khelpcenter-25.04.0-1.fc42.x86_64` on:

> Operating System: Fedora Linux 42  
> KDE Plasma Version: 6.3.4  
> KDE Frameworks Version: 6.13.0  
> Qt Version: 6.9.0  
> Kernel Version: 6.14.4-300.fc42.x86_64 (64-bit)  
> Graphics Platform: Wayland

> Graphics Processor 1: AMD Radeon RX 5700  
> Graphics Processor 2: AMD Radeon Graphics

ADDITIONAL INFORMATION

The version of KHC I'm using isn't listed in `enter_bug.cgi`'s `<select id="version">` field, so it's listed as "Unspecified".

[^1]: https://superuser.com/revisions/629766/1#content:~:text=That%20is%20called%20a%20%E2%80%9Cghost%20window%E2%80%9D
Comment 1 Roke Julian Lockhart Beedell 2025-04-30 18:13:43 UTC 
(In reply to Roke Julian Lockhart Beedell from comment #0)

If this isn't reproducible by the triage owner, I shan't be surprised if this is related to https://bugs.kde.org/attachment.cgi?id=178177&action=edit and/or https://bugs.kde.org/attachment.cgi?id=180786&action=edit.
Comment 2 Roke Julian Lockhart Beedell 2025-04-30 18:16:20 UTC 
(In reply to Roke Julian Lockhart Beedell from comment #0)

The strange behaviour isn't visible if a screenshot is captured via "Active Window" mode in Spectacle, as is usually the case. Perhaps that gives you a better idea of the cause.
Comment 3 Roke Julian Lockhart Beedell 2025-04-30 18:18:01 UTC 
Created attachment 180819 [details]
An "Active Window" Screenshot

(In reply to Roke Julian Lockhart Beedell from comment #2)

...Actually, it does: it's transparent in the screenshot!
Comment 4 Roke Julian Lockhart Beedell 2025-04-30 18:18:21 UTC 
Created attachment 180820 [details]
A "Full Screen" Screenshot
Comment 6 Roke Julian Lockhart Beedell 2025-05-01 09:25:39 UTC 
(In reply to John Kizer from comment #5)

Thanks! It is: https://discuss.kde.org/t/some-of-my-kde-apps-arent-working-properly/32522/21?u=rokejulianlockhart.