SUMMARY
Both the nightly and flathub stable Skrooge flatpaks crash at startup. The Fedora RPM package does not. My main .skg file last modifed April 3, suggesting this bug crept in since then, but I think neither the flatpak nor runtime has updated recently.

STEPS TO REPRODUCE
1.  In a terminal, run `SKGTRACE=3 flatpak run org.kde.skrooge//master`

OBSERVED RESULT
The Skrooge splash window appears, then there's a crash. In the terminal:
    ##  Loading plugin 18/25: Skrooge import and export plugin… from /app/lib/plugins/skg_gui/skrooge_importexport.so
    ##  FATAL: ASSERT failure in QList<T>::at: "index out of range", file /usr/include/QtCore/qlist.h, line 571

EXPECTED RESULT
No crash

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 
KDE Plasma Version: 6.3.4
KDE Frameworks Version: 6.12.0
Qt Version: 6.8.2 on Wayland

ADDITIONAL INFORMATION
Happens with no SKG URL, my regular .skg file, an old nearly empty one, and if I specify a bogus nosuchfile.skg on the command line.

Another KDE flatpak, org.speedcrunch.SpeedCrunch, also using the org.kde.Platform/x86_64/5.15-24.08
 runtime, does not crash.

% flatpak info org.kde.skrooge//master         
    ...
         Ref: app/org.kde.skrooge/x86_64/master
        Arch: x86_64
      Branch: master
     Version: 2.33.0
     License: GPL-2.0+
      Origin: skrooge-nightly
  Collection: 
Installation: system
   Installed: 203.1 MB
     Runtime: org.kde.Platform/x86_64/5.15-24.08
         Sdk: org.kde.Sdk/x86_64/5.15-24.08

      Commit: c7c9b2524dd2310c9cc6273127164d36a3e59087905bab5435921fc607d4cde9
     Subject: Export org.kde.skrooge
        Date: 2025-03-19 18:48:14 +0000

I'll try to debug the Flatpak crash, but first I have to do my U.S. taxes!