Bug 486028

Summary: Content of some (React/Nuxt/NodeJS based?) websites disappear after loaded
Product: [Applications] Falkon Reporter: acidrums4 <acidrums4+stuff>
Component: generalAssignee: Unassigned bugs mailing-list <unassigned-bugs>
Status: RESOLVED UPSTREAM    
Severity: grave CC: jurajoravec
Priority: NOR    
Version: 23.08.5   
Target Milestone: ---   
Platform: Fedora RPMs   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description acidrums4 2024-04-23 16:49:15 UTC 
SUMMARY
The content in some websites will suddenly disappear after its content is fully loaded, for example:

https://fedoraproject.org/workstation/download
https://www.olimpica.com/
https://www.specialized.com/

STEPS TO REPRODUCE
1. Open any of the websites aforementioned in Falkon.
2. Wait until they load.

OBSERVED RESULT
Their content will disappear all of a sudden without any clue (sans the specialized one, where they ask to see the console).

EXPECTED RESULT
Their content will be shown and the user can see and interact with it normally.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 6.8
KDE Plasma Version: 5.27.11
KDE Frameworks Version: 5.115.0
Qt Version: 5.15.13

ADDITIONAL INFORMATION
I could test this behavior on both my daily driver system (Gentoo) and with Fedora on a fresh-out-of-the-box installation. I'll get some weird errors that won't happen on other browsers while interacting with elements of certain websites, i.e. an everhour widget inside a Trello card no longer works due to a "ReferenceError: structuredClone is not defined" error.
Comment 1 Juraj 2024-04-23 18:55:00 UTC 
Hello,

I dare to say this is due to QtWebEngine in Qt5 being based on Chromium 87 (or something similar) which is "way too old" for current websites.

Falkon 23.08 is still based on Qt5 which would explain this.
Falkon 24.02+ should "fix" this by switching to Qt6 and thus newer version of QtWebEngine.

Best regards,
Juraj
Comment 2 acidrums4 2024-04-23 21:06:24 UTC 
> I dare to say this is due to QtWebEngine in Qt5 being based on Chromium 87
> (or something similar) which is "way too old" for current websites.

After being able to download Fedora 40 (while trying to do so is how I remembered abot this!) and installing Falkon on its live session, I can confirm that you were absolutely right - in Falkon 24.* this is not happening at all.

Alas KDE6 is still masked on Gentoo so I'm stuck with the "old" QtWebEngine 5.x.

I'm marking this as "Resolved upstream" as this was a thing from QtWebEngine. Thank you so much and sorry for the noise.