Application: kdenlive (19.03.70)

Qt Version: 5.11.1
Frameworks Version: 5.50.0
Operating System: Linux 4.18.0-13-generic x86_64
Distribution: Ubuntu 18.10

-- Information about the crash:
- What I was doing when the application crashed:
I open kdenlive from a saved project
I select a point in the time bar, 
I launh play (with space)

In the bugged zone some editions was made (but removed):
I made transitions:
- 2 clips separated with ~5seconds in the same time line
- I added a title clip in an upper time line. This clip overlap the 2 first clips pn few seconds
- I added two "composite" transitions

Since those editions, I had more and more crashes, then I tried by removing those transitions and title. Crashes are not gone.

I tried to re-encode clip sources with ffmeg. No change.

The crash can be reproduced every time.

-- Backtrace:
Application: Kdenlive (kdenlive), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
__GI___libc_read (fd=6, buf=0x7ffd0d5ffa38, nbytes=56) at ../sysdeps/unix/sysv/linux/read.c:26
[Current thread is 1 (Thread 0x7f4ead189940 (LWP 11891))]

Thread 25 (Thread 0x7f4e1a7fc700 (LWP 11929)):
#0  0x00007f4eb81c36a0 in __GI___nanosleep (requested_time=0x7f4e1a7fbc20, remaining=0x7f4e1a7fbc10) at ../sysdeps/unix/sysv/linux/nanosleep.c:28
#1  0x00007f4ea0df3af5 in  () at /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#2  0x00007f4ea0d327d3 in  () at /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#3  0x00007f4ea0d795ec in  () at /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#4  0x00007f4ea0deef89 in  () at /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#5  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 24 (Thread 0x7f4e1affd700 (LWP 11924)):
#0  0x00007f4eb79482eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f4e393bd9c0) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f4eb79482eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x7f4e393bda28, cond=0x7f4e393bd998) at pthread_cond_wait.c:502
#2  0x00007f4eb79482eb in __pthread_cond_wait (cond=0x7f4e393bd998, mutex=0x7f4e393bda28) at pthread_cond_wait.c:655
#3  0x00007f4e9b0bd55e in  () at /usr/lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#5  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 23 (Thread 0x7f4e1b7fe700 (LWP 11923)):
#0  0x00007f4eb79482eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f4e393bd810) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f4eb79482eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x7f4e393bd878, cond=0x7f4e393bd7e8) at pthread_cond_wait.c:502
#2  0x00007f4eb79482eb in __pthread_cond_wait (cond=0x7f4e393bd7e8, mutex=0x7f4e393bd878) at pthread_cond_wait.c:655
#3  0x00007f4e9b0bd55e in  () at /usr/lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#5  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 22 (Thread 0x7f4e1bfff700 (LWP 11922)):
#0  0x00007f4eb79482eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f4e393bd660) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f4eb79482eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x7f4e393bd6c8, cond=0x7f4e393bd638) at pthread_cond_wait.c:502
#2  0x00007f4eb79482eb in __pthread_cond_wait (cond=0x7f4e393bd638, mutex=0x7f4e393bd6c8) at pthread_cond_wait.c:655
#3  0x00007f4e9b0bd55e in  () at /usr/lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#5  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 21 (Thread 0x7f4e44a1c700 (LWP 11921)):
#0  0x00007f4eb79482eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f4e393bd4b0) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f4eb79482eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x7f4e393bd518, cond=0x7f4e393bd488) at pthread_cond_wait.c:502
#2  0x00007f4eb79482eb in __pthread_cond_wait (cond=0x7f4e393bd488, mutex=0x7f4e393bd518) at pthread_cond_wait.c:655
#3  0x00007f4e9b0bd55e in  () at /usr/lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#5  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 20 (Thread 0x7f4e4521d700 (LWP 11920)):
#0  0x00007f4eb79482eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f4e393bd300) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f4eb79482eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x7f4e393bd368, cond=0x7f4e393bd2d8) at pthread_cond_wait.c:502
#2  0x00007f4eb79482eb in __pthread_cond_wait (cond=0x7f4e393bd2d8, mutex=0x7f4e393bd368) at pthread_cond_wait.c:655
#3  0x00007f4e9b0bd55e in  () at /usr/lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#5  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 19 (Thread 0x7f4e4601e700 (LWP 11919)):
#0  0x00007f4eb79482eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x5626f9409354) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f4eb79482eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x5626f9409300, cond=0x5626f9409328) at pthread_cond_wait.c:502
#2  0x00007f4eb79482eb in __pthread_cond_wait (cond=0x5626f9409328, mutex=0x5626f9409300) at pthread_cond_wait.c:655
#3  0x00007f4ea800e98d in  () at /usr/lib/x86_64-linux-gnu/mlt/libmltsdl2.so
#4  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#5  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 18 (Thread 0x7f4e4681f700 (LWP 11918)):
#0  0x00007f4eaf52a7aa in pa_srbchannel_read () at /usr/lib/x86_64-linux-gnu/pulseaudio/libpulsecommon-12.2.so
#1  0x00007f4eaf526d20 in  () at /usr/lib/x86_64-linux-gnu/pulseaudio/libpulsecommon-12.2.so
#2  0x00007f4eaf529a7b in  () at /usr/lib/x86_64-linux-gnu/pulseaudio/libpulsecommon-12.2.so
#3  0x00007f4eaf529e19 in  () at /usr/lib/x86_64-linux-gnu/pulseaudio/libpulsecommon-12.2.so
#4  0x00007f4eaf52a66a in  () at /usr/lib/x86_64-linux-gnu/pulseaudio/libpulsecommon-12.2.so
#5  0x00007f4eb2ca8568 in pa_mainloop_dispatch () at /usr/lib/x86_64-linux-gnu/libpulse.so.0
#6  0x00007f4eb2ca883c in pa_mainloop_iterate () at /usr/lib/x86_64-linux-gnu/libpulse.so.0
#7  0x00007f4ea0dd2d17 in  () at /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#8  0x00007f4ea0d32836 in  () at /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#9  0x00007f4ea0d795ec in  () at /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#10 0x00007f4ea0deef89 in  () at /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#11 0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#12 0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 17 (Thread 0x7f4e5c895700 (LWP 11917)):
#0  0x00007f4eb79482eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f4e38074004) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f4eb79482eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x7f4e38074068, cond=0x7f4e38073fd8) at pthread_cond_wait.c:502
#2  0x00007f4eb79482eb in __pthread_cond_wait (cond=0x7f4e38073fd8, mutex=0x7f4e38074068) at pthread_cond_wait.c:655
#3  0x00007f4e9b0bd55e in  () at /usr/lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#5  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 16 (Thread 0x7f4e5d096700 (LWP 11916)):
#0  0x00007f4eb79482eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f4e38073e54) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f4eb79482eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x7f4e38073eb8, cond=0x7f4e38073e28) at pthread_cond_wait.c:502
#2  0x00007f4eb79482eb in __pthread_cond_wait (cond=0x7f4e38073e28, mutex=0x7f4e38073eb8) at pthread_cond_wait.c:655
#3  0x00007f4e9b0bd55e in  () at /usr/lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#5  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 15 (Thread 0x7f4e5d897700 (LWP 11915)):
#0  0x00007f4eb79482eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f4e38073ca0) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f4eb79482eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x7f4e38073d08, cond=0x7f4e38073c78) at pthread_cond_wait.c:502
#2  0x00007f4eb79482eb in __pthread_cond_wait (cond=0x7f4e38073c78, mutex=0x7f4e38073d08) at pthread_cond_wait.c:655
#3  0x00007f4e9b0bd55e in  () at /usr/lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#5  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 14 (Thread 0x7f4e5e098700 (LWP 11914)):
#0  0x00007f4eb79482eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f4e38073af0) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f4eb79482eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x7f4e38073b58, cond=0x7f4e38073ac8) at pthread_cond_wait.c:502
#2  0x00007f4eb79482eb in __pthread_cond_wait (cond=0x7f4e38073ac8, mutex=0x7f4e38073b58) at pthread_cond_wait.c:655
#3  0x00007f4e9b0bd55e in  () at /usr/lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#5  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 13 (Thread 0x7f4e5fdfb700 (LWP 11913)):
#0  0x00007f4eb79482eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f4e38073940) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f4eb79482eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x7f4e380739a8, cond=0x7f4e38073918) at pthread_cond_wait.c:502
#2  0x00007f4eb79482eb in __pthread_cond_wait (cond=0x7f4e38073918, mutex=0x7f4e380739a8) at pthread_cond_wait.c:655
#3  0x00007f4e9b0bd55e in  () at /usr/lib/x86_64-linux-gnu/libavcodec.so.58
#4  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#5  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 12 (Thread 0x7f4e5e8f9700 (LWP 11912)):
[KCrash Handler]
#6  0x00007f4ea0ac1364 in MltInput::set_pixel_data(unsigned char const*) () at /usr/lib/x86_64-linux-gnu/mlt/libmltopengl.so
#7  0x00007f4ea0abae68 in  () at /usr/lib/x86_64-linux-gnu/mlt/libmltopengl.so
#8  0x00007f4ea0aba859 in  () at /usr/lib/x86_64-linux-gnu/mlt/libmltopengl.so
#9  0x00007f4ea0abb640 in  () at /usr/lib/x86_64-linux-gnu/mlt/libmltopengl.so
#10 0x00007f4ebacaaf3e in mlt_frame_get_image () at /usr/lib/x86_64-linux-gnu/libmlt.so.6
#11 0x00007f4ebacc0879 in  () at /usr/lib/x86_64-linux-gnu/libmlt.so.6
#12 0x00007f4ebacaaedf in mlt_frame_get_image () at /usr/lib/x86_64-linux-gnu/libmlt.so.6
#13 0x00007f4ebacbdd7f in  () at /usr/lib/x86_64-linux-gnu/libmlt.so.6
#14 0x00005626f536f11d in  ()
#15 0x00007f4eb86a8c87 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#16 0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#17 0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 11 (Thread 0x7f4e5f5fa700 (LWP 11911)):
#0  0x00007f4eb79482eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x5626f8b13c6c) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f4eb79482eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x5626f8b13c18, cond=0x5626f8b13c40) at pthread_cond_wait.c:502
#2  0x00007f4eb79482eb in __pthread_cond_wait (cond=0x5626f8b13c40, mutex=0x5626f8b13c18) at pthread_cond_wait.c:655
#3  0x00007f4ebacbe0e3 in mlt_consumer_rt_frame () at /usr/lib/x86_64-linux-gnu/libmlt.so.6
#4  0x00007f4ea800ede3 in  () at /usr/lib/x86_64-linux-gnu/mlt/libmltsdl2.so
#5  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 10 (Thread 0x7f4e7c0e7700 (LWP 11910)):
#0  0x00007f4eb81f37d6 in __GI_ppoll (fds=0x5626f9d63810, nfds=3, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:39
#1  0x00007f4eb2ca8261 in pa_mainloop_poll () at /usr/lib/x86_64-linux-gnu/libpulse.so.0
#2  0x00007f4eb2ca882e in pa_mainloop_iterate () at /usr/lib/x86_64-linux-gnu/libpulse.so.0
#3  0x00007f4eb2ca88e0 in pa_mainloop_run () at /usr/lib/x86_64-linux-gnu/libpulse.so.0
#4  0x00007f4ea0dd2eef in  () at /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#5  0x00007f4ea0d795ec in  () at /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#6  0x00007f4ea0deef89 in  () at /usr/lib/x86_64-linux-gnu/libSDL2-2.0.so.0
#7  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#8  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 9 (Thread 0x7f4e7dae2700 (LWP 11903)):
#0  0x00007f4eb81eef64 in __GI___libc_read (fd=20, buf=0x7f4e7dae1a40, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:26
#1  0x00007f4eb2d88180 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f4eb2d4291f in g_main_context_check () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f4eb2d42df0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f4eb2d42f6c in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f4eb88a315b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f4eb885016b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f4eb869f0b6 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f4eb86a8c87 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#10 0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 8 (Thread 0x7f4e7e2e3700 (LWP 11902)):
#0  0x00007f4eb81eef64 in __GI___libc_read (fd=19, buf=0x7f4e7e2e2a40, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:26
#1  0x00007f4eb2d88180 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f4eb2d4291f in g_main_context_check () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f4eb2d42df0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f4eb2d42f6c in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f4eb88a315b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f4eb885016b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f4eb869f0b6 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f4eb86a8c87 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#10 0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 7 (Thread 0x7f4e7ffff700 (LWP 11899)):
#0  0x00007f4eb2d89509 in g_mutex_lock () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#1  0x00007f4eb2d41e50 in g_main_context_acquire () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f4eb2d42d05 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f4eb2d42f6c in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f4eb88a315b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f4eb885016b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f4eb869f0b6 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f4eb950a1f5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#8  0x00007f4eb86a8c87 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#10 0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 6 (Thread 0x7f4e8e3a1700 (LWP 11897)):
#0  0x00007f4eb81eef64 in __GI___libc_read (fd=14, buf=0x7f4e8e3a0a20, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:26
#1  0x00007f4eb2d88180 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f4eb2d4291f in g_main_context_check () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f4eb2d42df0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f4eb2d42f6c in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f4eb88a315b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f4eb885016b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f4eb869f0b6 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f4eb950a1f5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#9  0x00007f4eb86a8c87 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#10 0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#11 0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 5 (Thread 0x7f4e8eba2700 (LWP 11895)):
#0  0x00007f4eb79482eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x5626f73ebac8) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f4eb79482eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x5626f73eba78, cond=0x5626f73ebaa0) at pthread_cond_wait.c:502
#2  0x00007f4eb79482eb in __pthread_cond_wait (cond=0x5626f73ebaa0, mutex=0x5626f73eba78) at pthread_cond_wait.c:655
#3  0x00007f4e8f29546b in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#4  0x00007f4e8f2951d7 in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#5  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7f4ea9a63700 (LWP 11894)):
#0  0x00007f4eb81eef64 in __GI___libc_read (fd=7, buf=0x7f4ea9a62a10, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:26
#1  0x00007f4eb2d88180 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f4eb2d4291f in g_main_context_check () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f4eb2d42df0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f4eb2d42f6c in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f4eb88a315b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f4eb885016b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f4eb869f0b6 in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f4eba29b545 in  () at /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#9  0x00007f4eb86a8c87 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#10 0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#11 0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7f4eaaa3c700 (LWP 11893)):
#0  0x00007f4eb81f36d9 in __GI___poll (fds=0x7f4eaaa3bb78, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f4eb2c5e917 in  () at /usr/lib/x86_64-linux-gnu/libxcb.so.1
#2  0x00007f4eb2c6053a in xcb_wait_for_event () at /usr/lib/x86_64-linux-gnu/libxcb.so.1
#3  0x00007f4eabce6159 in  () at /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#4  0x00007f4eb86a8c87 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#6  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7f4ead185700 (LWP 11892)):
#0  0x00007f4eb79482eb in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f4eb7481090) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f4eb79482eb in __pthread_cond_wait_common (abstime=0x0, mutex=0x5626f701fe00, cond=0x7f4eb7481068) at pthread_cond_wait.c:502
#2  0x00007f4eb79482eb in __pthread_cond_wait (cond=0x7f4eb7481068, mutex=0x5626f701fe00) at pthread_cond_wait.c:655
#3  0x00007f4eb851383c in std::condition_variable::wait(std::unique_lock<std::mutex>&) () at /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#4  0x00007f4eb69af832 in  () at /usr/lib/x86_64-linux-gnu/libQt5WebKit.so.5
#5  0x00007f4eb69af949 in  () at /usr/lib/x86_64-linux-gnu/libQt5WebKit.so.5
#6  0x00007f4eb851963f in  () at /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#7  0x00007f4eb7942164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#8  0x00007f4eb81ffdef in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7f4ead189940 (LWP 11891)):
#0  0x00007f4eb81eef64 in __GI___libc_read (fd=6, buf=0x7ffd0d5ffa38, nbytes=56) at ../sysdeps/unix/sysv/linux/read.c:26
#1  0x00007f4eab674b88 in  () at /usr/lib/x86_64-linux-gnu/libICE.so.6
#2  0x00007f4eab679388 in _IceRead () at /usr/lib/x86_64-linux-gnu/libICE.so.6
#3  0x00007f4eab6794dc in _IceReadSkip () at /usr/lib/x86_64-linux-gnu/libICE.so.6
#4  0x00007f4eab88c308 in _SmcProcessMessage () at /usr/lib/x86_64-linux-gnu/libSM.so.6
#5  0x00007f4eab67d978 in IceProcessMessages () at /usr/lib/x86_64-linux-gnu/libICE.so.6
#6  0x00007f4eb887a6db in QMetaObject::activate(QObject*, int, int, void**) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f4eb8885f19 in QSocketNotifier::activated(int, QSocketNotifier::QPrivateSignal) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f4eb8886261 in QSocketNotifier::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f4eb9c3f4a1 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#10 0x00007f4eb9c46ae0 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#11 0x00007f4eb8851499 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#12 0x00007f4eb88a3d6a in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#13 0x00007f4eb2d42c3e in g_main_context_dispatch () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#14 0x00007f4eb2d42ed8 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#15 0x00007f4eb2d42f6c in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#16 0x00007f4eb88a3143 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#17 0x00007f4eabd77e51 in  () at /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#18 0x00007f4eb885016b in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#19 0x00007f4eb88582e2 in QCoreApplication::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#20 0x00005626f50d3de3 in  ()
#21 0x00007f4eb810909b in __libc_start_main (main=0x5626f50d2c60, argc=2, argv=0x7ffd0d6005b8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffd0d6005a8) at ../csu/libc-start.c:308
#22 0x00005626f50d463a in _start ()
[Inferior 1 (process 11891) detached]

Reported using DrKonqi