SUMMARY
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Since it is my first bug report here, hi everyone. (-: 

Version 23.08 - both from Fedora 39 repositories and Flathub - are crashing on startup. It displays startupscreen, but segfaults shortly after. I am working on useful crash report, because my skills in debugging QT applications are second to none. I will get there.

STEPS TO REPRODUCE
1. Install version 23.08 of Kdenlive.
2. It crashes everytime on startup.
3. Revert to version 23.04, which is working fine.

OBSERVED RESULT
$ kdenlive
QSocketNotifier: Can only be used with threads started with QThread
profilePath from appDir/../share:  "/usr/share/mlt-7/profiles"
meltPath from KdenliveSetting::meltPath:  ""
meltPath from profilePath/../../../bin:  "/usr/bin/melt-7"
Empty metadata for  "glsl.manager"
Empty metadata for  "telecide"
unsupported effect in group "frei0r.alpha0ps" : "/usr/share/kdenlive/effect-templates/secondary_color_correction.xml"

(kdenlive:15895): Gtk-WARNING **: 16:51:22.460: Theme parsing error: <data>:1:0: Expected a valid selector
kf.service.services: The desktop entry file "/usr/share/applications/qemu.desktop" has Type= "Application" but no Exec line
kf.service.sycoca: Invalid Service :  "/usr/share/applications/qemu.desktop"
kf.service.services: The desktop entry file "/usr/share/applications/org.freedesktop.Xwayland.desktop" has Type= "Application" but no Exec line
kf.service.sycoca: Invalid Service :  "/usr/share/applications/org.freedesktop.Xwayland.desktop"
kf.service.services: KServiceTypeTrader: serviceType "ThumbCreator" not found
QQmlEngine::setContextForObject(): Object already has a QQmlContext
QWidget::setMinimumSize: (effect_list/QDockWidget) Negative sizes (0,-1) are not possible
QWidget::setMinimumSize: (transition_list/QDockWidget) Negative sizes (0,-1) are not possible
Segmentation fault (core dumped)

EXPECTED RESULT

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: Fedora 39
(available in About System)
KDE Plasma Version: I am on Gnome/Wayland.
KDE Frameworks Version: 
Qt Version: 5.15.10 and 6.5.2 

ADDITIONAL INFORMATION
I was tracking this bug on https://bugzilla.redhat.com/show_bug.cgi?id=2242641 .