Created attachment 176450 [details]
Visualisation of the issue : elements in green boxes should be clickable

SUMMARY
When setting up a DAV resource with a self-signed certificate,
the "accept certificate" window becomes unresponsive, i.e. the buttons cannot be pressed, nor can the window be closed. 

STEPS TO REPRODUCE
1. Do all initial steps to set up a DAV resource 
2. Enter "Remote URL" to server with self-signed certificate
3. Click "Fetch"

OBSERVED RESULT
"accept certificate" window opens in an unresponsive state.

EXPECTED RESULT
"accept certificate" window ought to be functional.

SOFTWARE/OS VERSIONS
Windows: n/a
macOS: n/a
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: Debian testing and Fedora 41
KDE Plasma Version:  5.x up to 6.2.4
KDE Frameworks Version: 5.x up to 6.8.0 
Qt Version: 5.x up to 6.8.0

ADDITIONAL INFORMATION
By accepting the certificate through a different application (e.g. Dolphin : file server),
the problem can be worked around.