while running the app the gui crashes randomly. (the backtrace is in the additional info box below):

(gdb) run
Starting program: /usr/bin/kdenlive 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
Icon theme "breeze" not found.
kf5.kiconthemes: Couldn't find current icon theme, falling back to default.
kf5.kxmlgui: Registering action  "edit_select_all"  under new name  "select_all_tracks"
Removing cache at "/home/farid/.cache/kdenlive-thumbs.kcache"
0x228e460 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x23184a0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x2254940 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x2317c00 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x248f770 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x1c7a5f0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x1c7a8d0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x24a3a10 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x21ec410 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x24a64a0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x2241980 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x2243a40 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x22435a0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x1c69ac0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x1c7b6b0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x1c71410 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x1ef7c60 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x1c63150 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x1ef8900 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x1efbf80 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x1c6c560 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x1c69fb0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x24cf220 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x24d3a50 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x24f8240 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x24de0a0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x24cce40 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x2443150 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04b70) ): Attempt to set a screen on a child window.
0x228e460 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x2254940 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x2317c00 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x248f770 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x1c7a5f0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x1c7a8d0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x24a3a10 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x21ec410 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x24a64a0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x2241980 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x2243a40 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x22435a0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x1c69ac0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x1c7b6b0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x1c71410 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x1ef7c60 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x1c63150 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x1ef8900 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x1efbf80 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x1c6c560 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x1c69fb0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x24cf220 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x24d3a50 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x24f8240 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x24de0a0 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x24cce40 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
0x2443150 void QWindowPrivate::setTopLevelScreen(QScreen*, bool) ( QScreen(0xd04a80) ): Attempt to set a screen on a child window.
Removing cache at "/home/farid/.cache/kdenlive-thumbs.kcache"
// TRACTOR PROBLEM
[New Thread 0x7fffb290c700 (LWP 4497)]
QObject::connect: Cannot queue arguments of type 'QVector<qint16>'
(Make sure 'QVector<qint16>' is registered using qRegisterMetaType().)
[New Thread 0x7ffe877fe700 (LWP 4620)]
[Thread 0x7ffe877fe700 (LWP 4620) exited]
[Thread 0x7fffb290c700 (LWP 4497) exited]
[mp3 @ 0x7fffac210520] Header missing
true
true
true
true
[mp3 @ 0x7fffacb00ee0] Header missing
[swscaler @ 0x7ffe118cb880] Warning: data is not aligned! This can lead to a speedloss
[mp3 @ 0x7ffe46333da0] Header missing
QObject::connect: Cannot queue arguments of type 'QVector<qint16>'
(Make sure 'QVector<qint16>' is registered using qRegisterMetaType().)
"Trying to convert empty KLocalizedString to QString."
"Trying to convert empty KLocalizedString to QString."
"Trying to convert empty KLocalizedString to QString."
"Trying to convert empty KLocalizedString to QString."
"Trying to convert empty KLocalizedString to QString."
"Trying to convert empty KLocalizedString to QString."
"Trying to convert empty KLocalizedString to QString."
"Trying to convert empty KLocalizedString to QString."
"Trying to convert empty KLocalizedString to QString."
"Trying to convert empty KLocalizedString to QString."
// deleting CLIP:  1213 ,   QUrl( "file:///home/farid/Música/Cia Cabelo de Maria/Cantos de Trabalho/02 Semente de Mandioca.mp3" ) 
"Trying to convert empty KLocalizedString to QString."
"Trying to convert empty KLocalizedString to QString."
// deleting CLIP:  1592 ,   QUrl( "file:///home/farid/Música/Cia Cabelo de Maria/Cantos de Trabalho/02 Semente de Mandioca.mp3" ) 
[h264 @ 0xec6f3c0] Value 601,000000 for parameter 'colorspace' out of range [0 - 10]
QObject::connect: Cannot queue arguments of type 'QVector<qint16>'
(Make sure 'QVector<qint16>' is registered using qRegisterMetaType().)
"Trying to convert empty KLocalizedString to QString."
"Trying to convert empty KLocalizedString to QString."
// deleting CLIP:  584 ,   QUrl( "file:///home/farid/Gunga/Casa Moringa/Caravana Casa Moringa 2014/Virgilio-Edinaldo/Beco/MVI_2310.MOV" ) 
// deleting CLIP:  595 ,   QUrl( "file:///home/farid/Gunga/Casa Moringa/Caravana Casa Moringa 2014/Virgilio-Edinaldo/Ninho/MVI_2215.MOV" ) 
// deleting CLIP:  651 ,   QUrl( "file:///home/farid/Gunga/Casa Moringa/Caravana Casa Moringa 2014/Virgilio-Edinaldo/Ninho/MVI_2215.MOV" ) 
// deleting CLIP:  864 ,   QUrl( "file:///home/farid/Gunga/Casa Moringa/Caravana Casa Moringa 2014/Virgilio-Edinaldo/Ninho/MVI_2215.MOV" ) 

^C[New Thread 0x7ffded7f9700 (LWP 9483)]
[New Thread 0x7fff027fc700 (LWP 9482)]
[New Thread 0x7fff5dff3700 (LWP 9481)]
[New Thread 0x7fff70ff1700 (LWP 9480)]
[New Thread 0x7fff747f8700 (LWP 9479)]
[New Thread 0x7fff74ff9700 (LWP 9478)]
[New Thread 0x7ffe517fa700 (LWP 9477)]
[New Thread 0x7ffe50ff9700 (LWP 9476)]
[New Thread 0x7ffe2e7f4700 (LWP 9475)]
[New Thread 0x7ffe167fc700 (LWP 9474)]
[New Thread 0x7ffdf07f8700 (LWP 9473)]
[New Thread 0x7ffdefff7700 (LWP 9472)]
[New Thread 0x7ffdf0ff9700 (LWP 9471)]
[New Thread 0x7ffe4bfff700 (LWP 9470)]
[New Thread 0x7ffe75ffb700 (LWP 9468)]
[New Thread 0x7ffe307f8700 (LWP 9466)]
[New Thread 0x7ffe30ff9700 (LWP 9465)]
[New Thread 0x7ffe317fa700 (LWP 9464)]
[New Thread 0x7ffe31ffb700 (LWP 9463)]
[New Thread 0x7ffe76ffd700 (LWP 9462)]
[New Thread 0x7ffe757fa700 (LWP 9461)]
[New Thread 0x7ffe74ff9700 (LWP 9460)]
[New Thread 0x7ffe747f8700 (LWP 9459)]
[New Thread 0x7ffe71ffa700 (LWP 9458)]
[New Thread 0x7ffe77fff700 (LWP 9450)]
[New Thread 0x7ffe84ff9700 (LWP 9449)]
[New Thread 0x7fff6afe5700 (LWP 9448)]
[New Thread 0x7fff6b7e6700 (LWP 9447)]
[New Thread 0x7fff73ff7700 (LWP 9446)]
[New Thread 0x7fff737f6700 (LWP 9445)]
[New Thread 0x7ffe717f9700 (LWP 9444)]
[New Thread 0x7ffe527fc700 (LWP 9443)]
[New Thread 0x7ffe51ffb700 (LWP 9442)]
[New Thread 0x7fff6e7ec700 (LWP 8873)]
[New Thread 0x7fff707f0700 (LWP 8872)]
[New Thread 0x7fff717f2700 (LWP 8871)]
[New Thread 0x7fff71ff3700 (LWP 8870)]
[New Thread 0x7fff757fa700 (LWP 8869)]
[New Thread 0x7ffe3b7fe700 (LWP 8868)]
[New Thread 0x7ffe2dff3700 (LWP 8867)]
[New Thread 0x7ffe26ffd700 (LWP 8866)]
[New Thread 0x7ffe257fa700 (LWP 8865)]
[New Thread 0x7ffdd37fe700 (LWP 8701)]
[New Thread 0x7ffdd3fff700 (LWP 8700)]
[New Thread 0x7ffde4ff9700 (LWP 8699)]
[New Thread 0x7ffde57fa700 (LWP 8698)]
[New Thread 0x7ffde5ffb700 (LWP 8697)]
[New Thread 0x7ffde67fc700 (LWP 8696)]
[New Thread 0x7ffde6ffd700 (LWP 8695)]
[New Thread 0x7ffde77fe700 (LWP 8694)]
[New Thread 0x7ffde7fff700 (LWP 8693)]
[New Thread 0x7ffe767fc700 (LWP 8683)]
[New Thread 0x7ffe777fe700 (LWP 8682)]
[New Thread 0x7ffe877fe700 (LWP 8681)]
[New Thread 0x7ffe87fff700 (LWP 8680)]
[New Thread 0x7fff6dfeb700 (LWP 8679)]
[New Thread 0x7ffe70ff8700 (LWP 8678)]
[New Thread 0x7ffe38ff9700 (LWP 8677)]
[New Thread 0x7ffe337fe700 (LWP 8676)]
[New Thread 0x7ffe32ffd700 (LWP 8675)]
[New Thread 0x7fff767fc700 (LWP 8640)]
[New Thread 0x7fff76ffd700 (LWP 8639)]
[New Thread 0x7fff777fe700 (LWP 8638)]
[New Thread 0x7fff7cff9700 (LWP 8637)]
[New Thread 0x7fffb10f1700 (LWP 8636)]
[New Thread 0x7fffa5ffb700 (LWP 8635)]
[New Thread 0x7fffa4ff9700 (LWP 8634)]
[New Thread 0x7fff7d7fa700 (LWP 8633)]
[New Thread 0x7fff75ffb700 (LWP 8632)]
[New Thread 0x7ffdf17fa700 (LWP 8631)]
[New Thread 0x7ffdf1ffb700 (LWP 8630)]
[New Thread 0x7ffdf27fc700 (LWP 8629)]
[New Thread 0x7ffdf2ffd700 (LWP 8628)]
[New Thread 0x7ffdf37fe700 (LWP 8627)]
[New Thread 0x7ffe0d7fa700 (LWP 8626)]
[New Thread 0x7ffe4affd700 (LWP 8625)]
[New Thread 0x7ffe4b7fe700 (LWP 8624)]
[New Thread 0x7fff6bfe7700 (LWP 8623)]
[New Thread 0x7fff017fa700 (LWP 8610)]
[New Thread 0x7fff01ffb700 (LWP 8609)]
[New Thread 0x7fff6a7e4700 (LWP 8608)]
[New Thread 0x7fff7dffb700 (LWP 8607)]
[New Thread 0x7fffb9cf5700 (LWP 8606)]
[New Thread 0x7fffb94f4700 (LWP 8605)]
[New Thread 0x7fffb30f5700 (LWP 8604)]
[New Thread 0x7fffb28f4700 (LWP 8603)]
[New Thread 0x7fffb18f2700 (LWP 8602)]
[New Thread 0x7ffdedffa700 (LWP 8601)]
[New Thread 0x7ffdee7fb700 (LWP 8600)]
[New Thread 0x7ffdeeffc700 (LWP 8599)]
[New Thread 0x7ffdf3fff700 (LWP 8598)]
[New Thread 0x7ffdfcff9700 (LWP 8597)]
[New Thread 0x7ffdfd7fa700 (LWP 8596)]
[New Thread 0x7ffdfdffb700 (LWP 8595)]
[New Thread 0x7ffe0cff9700 (LWP 8594)]
[New Thread 0x7ffe0dffb700 (LWP 8593)]
[New Thread 0x7ffe0f7fe700 (LWP 8592)]
[New Thread 0x7ffe0ffff700 (LWP 8591)]
[New Thread 0x7ffe14ff9700 (LWP 8590)]
[New Thread 0x7ffe157fa700 (LWP 8589)]
[New Thread 0x7ffe15ffb700 (LWP 8588)]
[New Thread 0x7ffdfffff700 (LWP 8587)]
[New Thread 0x7ffdff7fe700 (LWP 8586)]
[New Thread 0x7ffdfeffd700 (LWP 8585)]
[New Thread 0x7ffdfe7fc700 (LWP 8584)]
[New Thread 0x7ffe2eff5700 (LWP 8574)]
[New Thread 0x7ffe327fc700 (LWP 8573)]
[New Thread 0x7ffe397fa700 (LWP 8572)]
[New Thread 0x7ffe52ffd700 (LWP 8571)]
[New Thread 0x7ffe8cff9700 (LWP 8570)]
[New Thread 0x7ffe53fff700 (LWP 8569)]
[New Thread 0x7ffe537fe700 (LWP 8568)]
[New Thread 0x7ffe0effd700 (LWP 8567)]
[New Thread 0x7ffe0e7fc700 (LWP 8566)]
[New Thread 0x7fff7e7fc700 (LWP 7850)]
[New Thread 0x7fff7effd700 (LWP 7849)]
[New Thread 0x7fff7f7fe700 (LWP 7848)]
[New Thread 0x7fff7ffff700 (LWP 7847)]
[New Thread 0x7fffb20f3700 (LWP 7846)]
[New Thread 0x7ffe2f7f6700 (LWP 7845)]
[New Thread 0x7ffe24ff9700 (LWP 7844)]
[New Thread 0x7ffe17fff700 (LWP 7843)]
[New Thread 0x7ffe177fe700 (LWP 7842)]
[New Thread 0x7fffa67fc700 (LWP 6918)]
[New Thread 0x7fffa6ffd700 (LWP 6917)]
[New Thread 0x7fffa77fe700 (LWP 6916)]
[New Thread 0x7fffa7fff700 (LWP 6915)]
[New Thread 0x7fffb08f0700 (LWP 6914)]
[New Thread 0x7fff6d7ea700 (LWP 6913)]
[New Thread 0x7fff6cfe9700 (LWP 6912)]
[New Thread 0x7fff6c7e8700 (LWP 6911)]
[New Thread 0x7fff69fe3700 (LWP 6910)]
[New Thread 0x7ffe277fe700 (LWP 6231)]
[New Thread 0x7ffe27fff700 (LWP 6230)]
[New Thread 0x7ffe2cff1700 (LWP 6229)]
[New Thread 0x7ffe2d7f2700 (LWP 6228)]
[New Thread 0x7ffe3affd700 (LWP 6227)]
[New Thread 0x7ffe3a7fc700 (LWP 6226)]
[New Thread 0x7ffe39ffb700 (LWP 6225)]
[New Thread 0x7ffe33fff700 (LWP 6224)]
[New Thread 0x7ffe2fff7700 (LWP 6223)]
[New Thread 0x7ffe737fd700 (LWP 5064)]
[New Thread 0x7fff5bfef700 (LWP 5063)]
[New Thread 0x7fff5c7f0700 (LWP 5062)]
[New Thread 0x7fff5cff1700 (LWP 5061)]
[New Thread 0x7fff5d7f2700 (LWP 5060)]
[New Thread 0x7fff5fff7700 (LWP 5059)]
[New Thread 0x7fff5f7f6700 (LWP 5058)]
[New Thread 0x7fff5eff5700 (LWP 5057)]
[New Thread 0x7fff5e7f4700 (LWP 5056)]
[New Thread 0x7ffe867fc700 (LWP 5045)]
[New Thread 0x7ffe86ffd700 (LWP 5044)]
[New Thread 0x7ffe8d7fa700 (LWP 5043)]
[New Thread 0x7ffedbfff700 (LWP 5042)]
[New Thread 0x7fff00ff9700 (LWP 5041)]
[New Thread 0x7ffe85ffb700 (LWP 5040)]
[New Thread 0x7ffe857fa700 (LWP 5039)]
[New Thread 0x7ffe72ffc700 (LWP 5038)]
[New Thread 0x7ffe727fb700 (LWP 5037)]
[New Thread 0x7ffed9ffb700 (LWP 4982)]
[New Thread 0x7ffeda7fc700 (LWP 4981)]
[New Thread 0x7ffedaffd700 (LWP 4980)]
[New Thread 0x7ffedb7fe700 (LWP 4979)]
[New Thread 0x7fff77fff700 (LWP 4978)]
[New Thread 0x7fff727f4700 (LWP 4977)]
[New Thread 0x7fff6ffef700 (LWP 4976)]
[New Thread 0x7fff6f7ee700 (LWP 4975)]
[New Thread 0x7fff6efed700 (LWP 4974)]
[New Thread 0x7fff62ffd700 (LWP 4882)]
[New Thread 0x7fff637fe700 (LWP 4881)]
[New Thread 0x7fff63fff700 (LWP 4880)]
[New Thread 0x7fff68fe1700 (LWP 4879)]
[New Thread 0x7fff697e2700 (LWP 4878)]
[New Thread 0x7fff627fc700 (LWP 4877)]
[New Thread 0x7fff61ffb700 (LWP 4876)]
[New Thread 0x7fff617fa700 (LWP 4875)]
[New Thread 0x7fff60ff9700 (LWP 4874)]
[New Thread 0x7fff577e6700 (LWP 4756)]
[New Thread 0x7fff57fe7700 (LWP 4755)]
[New Thread 0x7fff587e8700 (LWP 4754)]
[New Thread 0x7fff58fe9700 (LWP 4753)]
[New Thread 0x7fff5b7ee700 (LWP 4752)]
[New Thread 0x7fff5afed700 (LWP 4751)]
[New Thread 0x7fff5a7ec700 (LWP 4750)]
[New Thread 0x7fff59feb700 (LWP 4749)]
[New Thread 0x7fff597ea700 (LWP 4748)]
[New Thread 0x7fff52fdd700 (LWP 4747)]
[New Thread 0x7fff537de700 (LWP 4746)]
[New Thread 0x7fff53fdf700 (LWP 4745)]
[New Thread 0x7fff547e0700 (LWP 4744)]
[New Thread 0x7fff56fe5700 (LWP 4743)]
[New Thread 0x7fff567e4700 (LWP 4742)]
[New Thread 0x7fff55fe3700 (LWP 4741)]
[New Thread 0x7fff557e2700 (LWP 4740)]
[New Thread 0x7fff54fe1700 (LWP 4739)]
[New Thread 0x7fffc0b1f700 (LWP 4479)]
[New Thread 0x7fffc9533700 (LWP 4478)]
[New Thread 0x7fffe1b5f700 (LWP 4477)]



Reproducible: Always

Steps to Reproduce:
1. open kdenlive
2. do some editing
3. crash



(gdb) backtrace
#0  0x00007fffece7e55d in pthread_join () from /usr/lib/libpthread.so.0
#1  0x00007fffc465a377 in ?? () from /usr/lib/mlt/libmltsdl.so
#2  0x00007ffff6a07c27 in mlt_consumer_stop () from /usr/lib/libmlt.so.6
#3  0x00000000008dac2b in Render::switchPlay(bool) ()
#4  0x000000000081a662 in Monitor::slotPlay() ()
#5  0x00007ffff2699479 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/libQt5Core.so.5
#6  0x00007ffff2f45722 in QAction::triggered(bool) () from /usr/lib/libQt5Widgets.so.5
#7  0x00007ffff2f47d88 in QAction::activate(QAction::ActionEvent) () from /usr/lib/libQt5Widgets.so.5
#8  0x00007ffff2f483c7 in QAction::event(QEvent*) () from /usr/lib/libQt5Widgets.so.5
#9  0x00007ffff2f4facc in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQt5Widgets.so.5
#10 0x00007ffff2f54f10 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQt5Widgets.so.5
#11 0x00007ffff2668e6b in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQt5Core.so.5
#12 0x00007ffff29c105b in QShortcutMap::dispatchEvent(QKeyEvent*) () from /usr/lib/libQt5Gui.so.5
#13 0x00007ffff29c11b9 in QShortcutMap::tryShortcutEvent(QObject*, QKeyEvent*) () from /usr/lib/libQt5Gui.so.5
#14 0x00007ffff2f54d2f in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQt5Widgets.so.5
#15 0x00007ffff2668e6b in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQt5Core.so.5
#16 0x00007ffff29943e1 in QGuiApplicationPrivate::processKeyEvent(QWindowSystemInterfacePrivate::KeyEvent*) ()
   from /usr/lib/libQt5Gui.so.5
#17 0x00007ffff29992e5 in QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent*)
    () from /usr/lib/libQt5Gui.so.5
#18 0x00007ffff297e1ef in QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) ()
   from /usr/lib/libQt5Gui.so.5
#19 0x00007fffe430d1b0 in ?? () from /usr/lib/qt/plugins/platforms/libqxcb.so
#20 0x00007fffeaaa59fd in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#21 0x00007fffeaaa5ce0 in ?? () from /usr/lib/libglib-2.0.so.0
#22 0x00007fffeaaa5d8c in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#23 0x00007ffff26c1267 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) ()
   from /usr/lib/libQt5Core.so.5
#24 0x00007ffff2666902 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#25 0x00007ffff266e2dc in QCoreApplication::exec() () from /usr/lib/libQt5Core.so.5
#26 0x00000000004d7491 in main ()