Created attachment 166368 [details] a gdb debug log of kioworker crashing SUMMARY When I move files or do something that changes the thumbnail or generate a new one, kioworker will sometimes crash. Or randomly crashes entirely and I don't know why. *** NOTE: If you are reporting a crash, please try to attach a backtrace with debug symbols. See https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports *** STEPS TO REPRODUCE 1. Try moving files, or something that has to do with regenerating a thumbnail OBSERVED RESULT kioworker crashed EXPECTED RESULT kioworker not crashing SOFTWARE/OS VERSIONS Windows: macOS: Linux/KDE Plasma: Arch Linux (available in About System) KDE Plasma Version: 6.0.0 KDE Frameworks Version: 6.0.0 Qt Version: 6.7.0 ADDITIONAL INFORMATION My Arch Linux installation has testing and kde-unstable repositories enabled.
What seems to happen is: - A thumbnail for a kdenlive file is requested - The mltthumbnailer (build against Qt6) is activated - At some point that loads libmltqt.so and creates a QApplication - libmltqt.so is built against Qt5 - Now we are mixing Qt5 and Qt6 in the same process, which causes problems Not sure whether it's expected that the mlt thumbnailer creates/needs a QApplication. But it looks like a packaging issue that MLT with Qt5 is used with Qt6 Kdenlive
*** Bug 482631 has been marked as a duplicate of this bug. ***
A possibly relevant merge request was started @ https://invent.kde.org/multimedia/kdenlive/-/merge_requests/472
Git commit 56cb0ef567cacf4a87964cd51a53371fbc109470 by Antonio Rojas. Committed on 07/03/2024 at 13:00. Pushed by nicolasfella into branch 'master'. Block Qt5 MLT plugins in thumbnailer when building with Qt6. Follow up to a3d52b2b3258a9c250dd3ad27d618d024beee4c6 M +5 -0 thumbnailer/mltpreview.cpp https://invent.kde.org/multimedia/kdenlive/-/commit/56cb0ef567cacf4a87964cd51a53371fbc109470
Git commit ca01d111e8868e2657e7271ea58ae1469a1b8e34 by Nicolas Fella, on behalf of Antonio Rojas. Committed on 07/03/2024 at 16:17. Pushed by nicolasfella into branch 'release/24.02'. Block Qt5 MLT plugins in thumbnailer when building with Qt6. Follow up to a3d52b2b3258a9c250dd3ad27d618d024beee4c6 (cherry picked from commit 56cb0ef567cacf4a87964cd51a53371fbc109470) M +5 -0 thumbnailer/mltpreview.cpp https://invent.kde.org/multimedia/kdenlive/-/commit/ca01d111e8868e2657e7271ea58ae1469a1b8e34