kdenlive-20.04.2 aborts on 11.3

[Simon Gerraty]

I had to downgrade kdenlive from 19.12 to 18.x due to unusable UI
[kdenlive] [Bug 417031]

I recently had to pkg upgrade, so now have kdenlive-20.04.2
which just aborts.

The stack trace does not look very helpful, except to show we die in Qt
(see below), also lots of warning/errors about things blacklisted:

kdenlive
"gtkrescale" is blacklisted
"rgblut" is blacklisted
"spot_remover" is blacklisted
"text" is blacklisted
"timer" is blacklisted
"burningtv" is blacklisted
WARNING : Fails to parse  "telecide"
"resample" is blacklisted
WARNING : Fails to parse  "audiochannels"
WARNING : Fails to parse  "audioconvert"
WARNING : Fails to parse  "data_feed"
"data_show" is blacklisted
WARNING : Fails to parse  "imageconvert"
"mask_apply" is blacklisted
"mask_start" is blacklisted
"mono" is blacklisted
"region" is blacklisted
"resize" is blacklisted
"transition" is blacklisted
"watermark" is blacklisted
WARNING : Fails to parse  "glsl.manager"
WARNING : Fails to parse  "movit.convert"
WARNING : Fails to parse  "movit.crop"
WARNING : Fails to parse  "movit.resample"
WARNING : Fails to parse  "movit.resize"
"qtext" is blacklisted
"motion_est" is blacklisted
WARNING : Fails to parse  "crop_detect"
"videostab" is blacklisted
"videostab2" is blacklisted
WARNING : Fails to parse  "avcolour_space"
WARNING : Fails to parse  "avcolor_space"
WARNING : Fails to parse  "avdeinterlace"
WARNING : Fails to parse  "swscale"
"avfilter.abench" is blacklisted
"avfilter.acompressor" is blacklisted
"avfilter.adelay" is blacklisted
[lots more skipped]
"frei0r.vertigo" is blacklisted
WARNING : Fails to parse  "deinterlace"
++++++ Unknown asset :  "avfilter.acompressor"
++++++ Unknown asset :  "avfilter.aecho"
++++++ Unknown asset :  "avfilter.agate"
Warning: duplicate custom definition of effect "frei0r.alpha0ps" found. Only last one will be considered. Duplicate found in "/usr/local/share/kdenlive/effects/frei0r_alpha0ps.xml"
Warning: duplicate custom definition of effect "frei0r.balanc0r" found. Only last one will be considered. Duplicate found in "/usr/local/share/kdenlive/effects/frei0r_balanc0r.xml"
Warning: duplicate custom definition of effect "frei0r.curves" found. Only last one will be considered. Duplicate found in "/usr/local/share/kdenlive/effects/frei0r_curves.xml"
Warning: duplicate custom definition of effect "frei0r.levels" found. Only last one will be considered. Duplicate found in "/usr/local/share/kdenlive/effects/frei0r_levels.xml"
Warning: duplicate custom definition of effect "frei0r.lightgraffiti" found. Only last one will be considered. Duplicate found in "/usr/local/share/kdenlive/effects/frei0r_lightgraffiti.xml"
Warning: duplicate custom definition of effect "frei0r.select0r" found. Only last one will be considered. Duplicate found in "/usr/local/share/kdenlive/effects/frei0r_select0r.xml"
Warning: duplicate custom definition of effect "frei0r.sopsat" found. Only last one will be considered. Duplicate found in "/usr/local/share/kdenlive/effects/frei0r_sopsat.xml"
++++++ Unknown asset :  "frei0r.tehRoxx0r"
++++++ Unknown asset :  "frei0r.vertigo"
++++++ Unknown asset :  "frei0r.vertigo"
++++++ Unknown asset :  "movit.unsharp_mask"
Warning: duplicate custom definition of effect "qtblend" found. Only last one will be considered. Duplicate found in "/usr/local/share/kdenlive/effects/qtblend.xml"
++++++ Unknown asset :  "region"
++++++ Unknown asset :  "timewarp"
++++++ Unknown asset :  "opencv.tracker"
++++++ Unknown asset :  "opencv.tracker"
"frei0r.alphainjection" is blacklisted
"frei0r.blend" is blacklisted
"frei0r.composition" is blacklisted
"frei0r.xfade0r" is blacklisted
QGLXContext: Failed to create dummy context
Failed to create OpenGL context for format QSurfaceFormat(version 2.0, options QFlags<QSurfaceFormat::FormatOption>(), depthBufferSize 24, redBufferSize -1, greenBufferSize -1, blueBufferSize -1, alphaBufferSize -1, stencilBufferSize 8, samples -1, swapBehavior QSurfaceFormat::DoubleBuffer, swapInterval 1, colorSpace QSurfaceFormat::DefaultColorSpace, profile  QSurfaceFormat::NoProfile) 
Abort (core dumped) 


(lldb) target create "/usr/local/bin/kdenlive" --core "kdenlive.core"
Core file '/tmp/kdenlive.core' (x86_64) was loaded.
(lldb) bt
* thread #1, name = 'kdenlive', stop reason = signal SIGABRT
  * frame #0: 0x000000080ed5d9ba libc.so.7`thr_kill + 10
    frame #1: 0x000000080ed5d984 libc.so.7`__raise(s=6) at raise.c:52:10
    frame #2: 0x000000080ed5d8f9 libc.so.7`abort at abort.c:65:8
    frame #3: 0x000000080dcae949 libQt5Core.so.5`___lldb_unnamed_symbol156$$libQt5Core.so.5 + 9
    frame #4: 0x000000080dcaffae libQt5Core.so.5`QMessageLogger::fatal(char const*, ...) const + 202
    frame #5: 0x00000008063496b9 libQt5QuickWidgets.so.5`___lldb_unnamed_symbol22$$libQt5QuickWidgets.so.5 + 409
    frame #6: 0x0000000806349962 libQt5QuickWidgets.so.5`___lldb_unnamed_symbol23$$libQt5QuickWidgets.so.5 + 578
    frame #7: 0x000000080634a549 libQt5QuickWidgets.so.5`QQuickWidget::resizeEvent(QResizeEvent*) + 617
    frame #8: 0x00000008085b6d6f libQt5Widgets.so.5`QWidget::event(QEvent*) + 1167
    frame #9: 0x000000080634b7da libQt5QuickWidgets.so.5`QQuickWidget::event(QEvent*) + 810
    frame #10: 0x000000080857ba10 libQt5Widgets.so.5`QApplicationPrivate::notify_helper(QObject*, QEvent*) + 272
    frame #11: 0x000000080857cfcc libQt5Widgets.so.5`QApplication::notify(QObject*, QEvent*) + 620
    frame #12: 0x000000080de9d792 libQt5Core.so.5`QCoreApplication::notifyInternal2(QObject*, QEvent*) + 210
    frame #13: 0x00000008085af59e libQt5Widgets.so.5`QWidgetPrivate::sendPendingMoveAndResizeEvents(bool, bool) + 286
    frame #14: 0x00000008085b5867 libQt5Widgets.so.5`QWidgetPrivate::show_helper() + 55
    frame #15: 0x00000008085b5c62 libQt5Widgets.so.5`QWidgetPrivate::showChildren(bool) + 386
    frame #16: 0x00000008085b5889 libQt5Widgets.so.5`QWidgetPrivate::show_helper() + 89
    frame #17: 0x00000008085b5c62 libQt5Widgets.so.5`QWidgetPrivate::showChildren(bool) + 386
    frame #18: 0x00000008085b5889 libQt5Widgets.so.5`QWidgetPrivate::show_helper() + 89
    frame #19: 0x00000008085b6715 libQt5Widgets.so.5`QWidgetPrivate::setVisible(bool) + 837