Bug 469624

SUMMARY
***
when a custom effect from previous version is drag and dropped to a video, KDENlive crahes
***


STEPS TO REPRODUCE
1. custom effet from an older version
2. add a video in tineline
3. drag the custom effect to the video

OBSERVED RESULT
crahes without warning

EXPECTED RESULT
add the custom effect to the video

SOFTWARE/OS VERSIONS

Système d'exploitation : Debian GNU/Linux 11
Version de KDE Plasma : 5.20.5
Version de KDE Frameworks : 5.78.0
Version de Qt : 5.15.2
Version de noyau : 5.10.0-20-amd64
Type de système d'exploitation : 64-bit
Processeurs : 4 × Intel® Core™ i7-6500U CPU @ 2.50GHz
Mémoire : 11,6 Gio de mémoire vive
Processeur graphique : Mesa Intel® HD Graphics 520

ADDITIONAL INFORMATION
flatpak version is used kosole gives this info after drag and drop :

qml: [kdenlive/effect]
qml: Add effect:  gala2019
XML parsing of  "gala2019" . found 3 parameters
 = = SET EFFECT PARAM:  "0"  =  0,5
 = = SET EFFECT PARAM:  "4"  =  1
kf.i18n: Trying to convert empty KLocalizedString to QString.
 = = SET EFFECT PARAM:  "5"  =  -1,35179;-0,415528#0;0#0,529752;0,162841|0,817355;0,872678#1;1#2,16014;1,80874
END parsing of  "gala2019" . Number of found parameters 3
// GOT CLIP STACK DATA CHANGE:  QVector(308)
// GOT CLIP STACK DATA CHANGE DONE:  QModelIndex(0,0,0xa,TimelineItemModel(0x7f0658008460))  =  QVector(308)
MUTEX LOCK!!!!!!!!!!!! loadEffects COUNT:  4
// FOUND ADDED PARAM
QLocale: Could not load double parameter ""
QLocale: Could not load double parameter ""
// FOUND ADDED PARAM
got pixmap that is not null
QLayout: Attempting to add QLayout "" to KeyframeWidget "", which already has a layout
QLocale: Could not load double parameter ""
MUTEX UNLOCK!!!!!!!!!!!! loadEffects
qml: item not found
deleting collapsibleeffectview
deleting collapsibleeffectview
deleting collapsibleeffectview
free(): invalid next size (normal)