Bug 474154

SUMMARY
Kdenlive is crashing whenever I try to click between clips with effects. More accruately, if I've clicked on a clip with an effect, then the next clip that I click on that also has an effect will cause the application to crash. So if I click on clip 1 with an effect then click on clip 2 that has nothing, it won't crash, but then if I click on clip 3 that has an effect, Kdenlive will freeze as it's trying to load whatever effect it is, then will crash.

This bug originally occurred for me on a 23.08.0 Flatpak install, but the issue persisted when I downgraded to 23.04.3 and even when I tried AppImages of different versions.

***Backtrace and extra gdb context:
// SHOW KEYFRAMES:  true
MUTEX LOCK!!!!!!!!!!!! setmodel
MUTEX UNLOCK!!!!!!!!!!!! setmodel
MUTEX LOCK!!!!!!!!!!!! loadEffects COUNT:  1
// // // RESULTING REQUIRED SCENE:  1
MUTEX UNLOCK!!!!!!!!!!!! loadEffects
-----
// SHOW KEYFRAMES:  true
deleting collapsibleeffectview
terminate called after throwing an instance of 'std::out_of_range'
  what():  unordered_map::at

Thread 1 "kdenlive" received signal SIGABRT, Aborted.
0x00007ffff4a6f204 in __pthread_kill_implementation () from /usr/lib/x86_64-linux-gnu/libc.so.6
(gdb) thread apply all bt full

Thread 222 (Thread 0x7ffe8effd640 (LWP 257) "QQuickContext2D"):
Couldn't get registers: No such process.
(gdb) 


STEPS TO REPRODUCE
1. Make a new Kdenlive project.
2. Import two different clips of whatever kind (video/image/audio) into the project bin.
3. Apply an effect to both clips.
4. Click between them.


OBSERVED RESULT
Kdenlive freezes then crashes.


EXPECTED RESULT
The effects of the selected clip load successfully in the Effect/Composition Stack window.


SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Linux Mint 21.1
KDE Frameworks Version: 5.109.0
Qt Version: 5.15.10
MLT Version: 7.15.0