SUMMARY

I use Okular as Flatpak from Flathub on Fedora 39 Workstation (Beta). It crashes when I save an existing file, but works as expected, when I choose "Save as" and use a new filename. (Save as with overwrite crashs as well). 

STEPS TO REPRODUCE
1. Open a PDF file in Okular 
2. Add some annotations
3. Press Ctrl+S or save the file

OBSERVED RESULT

Okular crashes


$ flatpak run org.kde.okular 
QSocketNotifier: Can only be used with threads started with QThread
qt.qpa.qgnomeplatform: Could not find color scheme  ""
kf.kio.widgets: Failed to check which JobView API is supported "org.freedesktop.DBus.Error.ServiceUnknown"
kf.kio.workers.file: copy() QUrl("file:///run/flatpak/app/org.kde.okular/okular.sQwDeP") to QUrl("file:///home/keywan/Dokumente/test.pdf") mode= -1



EXPECTED RESULT

It saves the file.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Fedora 39 Workstation (Beta)  with Gnome 45
(available in About System)
KDE Plasma Version: flatpak org.kde.Platform/x86_64/5.15-22.08
KDE Frameworks Version: flatpak org.kde.Platform/x86_64/5.15-22.08
Qt Version: flatpak 

$ flatpak list --runtime |  grep kde
Adwaita theme	org.kde.KStyle.Adwaita		5.15-21.08	flathub	system
Adwaita theme	org.kde.KStyle.Adwaita		5.15-22.08	flathub	system
Adwaita theme	org.kde.KStyle.Adwaita		6.5	flathub	system
KDE Application Platform	org.kde.Platform		5.15-21.08	flathub	system
KDE Application Platform	org.kde.Platform		5.15-22.08	flathub	system
KDE Application Platform	org.kde.Platform		6.5	flathub	system
QGnomePlatform	org.kde.PlatformTheme.QGnomePlatform		5.15-21.08	flathub	system
QGnomePlatform	org.kde.PlatformTheme.QGnomePlatform		5.15-22.08	flathub	system
QGnomePlatform	org.kde.PlatformTheme.QGnomePlatform		6.5	flathub	system
QtSNI	org.kde.PlatformTheme.QtSNI		5.15-21.08	flathub	system
KDE Software Development Kit	org.kde.Sdk		5.15-22.08	flathub	system
QGnomePlatform-decoration	org.kde.WaylandDecoration.QGnomePlatform-decoration		5.15-21.08	flathub	system
QGnomePlatform-decoration	org.kde.WaylandDecoration.QGnomePlatform-decoration		5.15-22.08	flathub	system
QGnomePlatform-decoration	org.kde.WaylandDecoration.QGnomePlatform-decoration		6.5	flathub	system

ADDITIONAL INFORMATION
It crashes when I save an existing file, but works as expected, when I choose "Save as" and use a new filename. (Save as with overwrite crashs as well). 

I tried different PDF files and locatations. Always when it needs to write an existing files, it crashes. It worked fine with Gnome 44 and earlier.