Bug 403714

Summary: Preview Pane Constantly Flashes (WebEngine issue)
Product: [Applications] kmail2 Reporter: Dan <dan.f.kriz>
Component: generalAssignee: kdepim bugs <kdepim-bugs>
Status: REPORTED ---    
Severity: major CC: dan.f.kriz
Priority: NOR    
Version: unspecified   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description Dan 2019-01-28 21:34:34 UTC 
Application: kmail (5.10.1)

Qt Version: 5.12.0
Frameworks Version: 5.54.0
Operating System: Linux 4.20.4-arch1-1-ARCH x86_64
Distribution (Platform): Archlinux Packages

-- Information about the crash:
I open kmail.
The preview pane flashes constantly, and is unable to preview any emails.
This appears to be a bug in qt5-webengine. I can reproduce this by browsing to any URL in Konqueror when WebEngine is used, but
things show fine when using KHTML.
If I attempt to close Kmail when the preview pane is flashing, I get this crash.

The crash can be reproduced every time.

-- Backtrace:
Application: KMail (kmail), signal: Segmentation fault
Using host libthread_db library "/usr/lib/libthread_db.so.1".
[Current thread is 1 (Thread 0x7fcdfdebfb40 (LWP 3647))]

Thread 26 (Thread 0x7fccf2350700 (LWP 3738)):
#0  0x00007fce15384ef6 in pthread_cond_timedwait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#1  0x00007fce0eafc447 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#2  0x00007fce0eafd16a in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#3  0x00007fce0eafd252 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#4  0x00007fce0eabc301 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#5  0x00007fce0eabe4d7 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#6  0x00007fce0eabeac4 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#7  0x00007fce0eaff361 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#8  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#9  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 25 (Thread 0x7fcdceffd700 (LWP 3737)):
#0  0x00007fce15384ef6 in pthread_cond_timedwait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#1  0x00007fce0eafc447 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#2  0x00007fce0eafd16a in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#3  0x00007fce0eafd252 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#4  0x00007fce0eabc301 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#5  0x00007fce0eabe806 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#6  0x00007fce0eabeac4 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#7  0x00007fce0eaff361 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#8  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#9  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 24 (Thread 0x7fcd796ee700 (LWP 3704)):
#0  0x00007fce15384afc in pthread_cond_wait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#1  0x00007fce0b9b728c in ?? () from /usr/lib/libQt5Script.so.5
#2  0x00007fce0b9b72a9 in ?? () from /usr/lib/libQt5Script.so.5
#3  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#4  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 23 (Thread 0x7fcda0ad3700 (LWP 3691)):
#0  0x00007fce14465424 in g_mutex_unlock () from /usr/lib/libglib-2.0.so.0
#1  0x00007fce144b5faa in g_main_context_check () from /usr/lib/libglib-2.0.so.0
#2  0x00007fce144b74e6 in ?? () from /usr/lib/libglib-2.0.so.0
#3  0x00007fce144b762e in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#4  0x00007fce17ee75c4 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#5  0x00007fce17e9058c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#6  0x00007fce17cd45c9 in QThread::exec() () from /usr/lib/libQt5Core.so.5
#7  0x00007fce17cd59cc in ?? () from /usr/lib/libQt5Core.so.5
#8  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#9  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 22 (Thread 0x7fcda1da4700 (LWP 3688)):
#0  0x00007fce15384afc in pthread_cond_wait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#1  0x00007fce0eafc379 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#2  0x00007fce0eafd178 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#3  0x00007fce0eafd20f in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#4  0x00007fce0eabc318 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#5  0x00007fce0eabe806 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#6  0x00007fce0eabeb44 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#7  0x00007fce0eaff361 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#8  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#9  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 21 (Thread 0x7fcda27fc700 (LWP 3682)):
#0  0x00007fce15384e5b in pthread_cond_timedwait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#1  0x00007fce14f56ea4 in ?? () from /usr/lib/nvidia/libGL.so.1
#2  0x00007fce09bca522 in ?? () from /usr/lib/nvidia/libnvidia-glcore.so.340.107
#3  0x00007fce14f56db4 in ?? () from /usr/lib/nvidia/libGL.so.1
#4  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#5  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 20 (Thread 0x7fcda2ffd700 (LWP 3681)):
#0  0x00007fce179b07a4 in read () from /usr/lib/libc.so.6
#1  0x00007fce02e85782 in pa_read () from /usr/lib/pulseaudio/libpulsecommon-12.2.so
#2  0x00007fce060f255f in pa_mainloop_prepare () from /usr/lib/libpulse.so.0
#3  0x00007fce060f2fd1 in pa_mainloop_iterate () from /usr/lib/libpulse.so.0
#4  0x00007fce060f3091 in pa_mainloop_run () from /usr/lib/libpulse.so.0
#5  0x00007fce061015ae in ?? () from /usr/lib/libpulse.so.0
#6  0x00007fce02eb59fc in ?? () from /usr/lib/pulseaudio/libpulsecommon-12.2.so
#7  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#8  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 19 (Thread 0x7fcda37fe700 (LWP 3680)):
#0  0x00007fce179cd12b in __lll_lock_wait_private () from /usr/lib/libc.so.6
#1  0x00007fce179cef38 in __fprintf_chk () from /usr/lib/libc.so.6
#2  0x00007fce058c72f0 in event_logv_ () from /usr/lib/libevent-2.1.so.6
#3  0x00007fce058c74b7 in event_warn () from /usr/lib/libevent-2.1.so.6
#4  0x00007fce058c8ee2 in ?? () from /usr/lib/libevent-2.1.so.6
#5  0x00007fce058beac8 in event_base_loop () from /usr/lib/libevent-2.1.so.6
#6  0x00007fce0eaffe29 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#7  0x00007fce0ea9b63b in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#8  0x00007fce0eace608 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#9  0x00007fce0eaff361 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#10 0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#11 0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 18 (Thread 0x7fcda3fff700 (LWP 3679)):
#0  0x00007fce15384afc in pthread_cond_wait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#1  0x00007fce0eafc379 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#2  0x00007fce0eafd178 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#3  0x00007fce0eafd20f in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#4  0x00007fce0ea7793f in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#5  0x00007fce0ea9b63b in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#6  0x00007fce0eace608 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#7  0x00007fce0eaff361 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#8  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#9  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 17 (Thread 0x7fcdccff9700 (LWP 3678)):
#0  0x00007fce15384ef6 in pthread_cond_timedwait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#1  0x00007fce0eafc447 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#2  0x00007fce0eafd16a in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#3  0x00007fce0ea77950 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#4  0x00007fce0ea9b63b in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#5  0x00007fce0eace608 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#6  0x00007fce0eaff361 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#7  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#8  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 16 (Thread 0x7fcdcd7fa700 (LWP 3677)):
#0  0x00007fce15384afc in pthread_cond_wait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#1  0x00007fce0eafc379 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#2  0x00007fce0f3d4ee8 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#3  0x00007fce0eace8cf in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#4  0x00007fce0eaff361 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#5  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#6  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 15 (Thread 0x7fcdcdffb700 (LWP 3676)):
#0  0x00007fce15384afc in pthread_cond_wait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#1  0x00007fce0eafc379 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#2  0x00007fce0eafd178 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#3  0x00007fce0eafd20f in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#4  0x00007fce0eabc318 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#5  0x00007fce0eabe4d7 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#6  0x00007fce0eabeb04 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#7  0x00007fce0eaff361 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#8  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#9  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 14 (Thread 0x7fcdce7fc700 (LWP 3675)):
#0  0x00007fce179b084f in write () from /usr/lib/libc.so.6
#1  0x00007fce1794085d in _IO_file_write@@GLIBC_2.2.5 () from /usr/lib/libc.so.6
#2  0x00007fce1793fbbf in new_do_write () from /usr/lib/libc.so.6
#3  0x00007fce17940f96 in __GI__IO_file_xsputn () from /usr/lib/libc.so.6
#4  0x00007fce17917732 in buffered_vfprintf () from /usr/lib/libc.so.6
#5  0x00007fce17914c12 in vfprintf () from /usr/lib/libc.so.6
#6  0x00007fce179cef8a in __fprintf_chk () from /usr/lib/libc.so.6
#7  0x00007fce058c72f0 in event_logv_ () from /usr/lib/libevent-2.1.so.6
#8  0x00007fce058c74b7 in event_warn () from /usr/lib/libevent-2.1.so.6
#9  0x00007fce058c8ee2 in ?? () from /usr/lib/libevent-2.1.so.6
#10 0x00007fce058beac8 in event_base_loop () from /usr/lib/libevent-2.1.so.6
#11 0x00007fce0eaffe29 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#12 0x00007fce0ea9b63b in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#13 0x00007fce0e44dce4 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#14 0x00007fce0eace6d8 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#15 0x00007fce0eaff361 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#16 0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#17 0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 13 (Thread 0x7fcdcf7fe700 (LWP 3673)):
#0  0x00007fce15384ef6 in pthread_cond_timedwait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#1  0x00007fce0eafc447 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#2  0x00007fce0eafd16a in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#3  0x00007fce0eafd252 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#4  0x00007fce0eabc301 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#5  0x00007fce0eabe806 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#6  0x00007fce0eabeac4 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#7  0x00007fce0eaff361 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#8  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#9  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 12 (Thread 0x7fcdcffff700 (LWP 3672)):
#0  0x00007fce15384ef6 in pthread_cond_timedwait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#1  0x00007fce0eafc447 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#2  0x00007fce0eafd16a in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#3  0x00007fce0eafd252 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#4  0x00007fce0eabc301 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#5  0x00007fce0eabe806 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#6  0x00007fce0eabeac4 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#7  0x00007fce0eaff361 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#8  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#9  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 11 (Thread 0x7fcddc807700 (LWP 3671)):
#0  0x00007fce15384ef6 in pthread_cond_timedwait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#1  0x00007fce0eafc447 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#2  0x00007fce0eafd16a in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#3  0x00007fce0eafd252 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#4  0x00007fce0eabc301 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#5  0x00007fce0eabe806 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#6  0x00007fce0eabeac4 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#7  0x00007fce0eaff361 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#8  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#9  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 10 (Thread 0x7fcddd008700 (LWP 3670)):
#0  0x00007fce178f60e2 in __dcigettext () from /usr/lib/libc.so.6
#1  0x00007fce1794d600 in strerror_r () from /usr/lib/libc.so.6
#2  0x00007fce1794d530 in strerror () from /usr/lib/libc.so.6
#3  0x00007fce058c74a3 in event_warn () from /usr/lib/libevent-2.1.so.6
#4  0x00007fce058c8ee2 in ?? () from /usr/lib/libevent-2.1.so.6
#5  0x00007fce058beac8 in event_base_loop () from /usr/lib/libevent-2.1.so.6
#6  0x00007fce0eaffe29 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#7  0x00007fce0ea9b63b in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#8  0x00007fce0eac0fd4 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#9  0x00007fce0eace6d8 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#10 0x00007fce0eaff361 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#11 0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#12 0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 9 (Thread 0x7fcdde00a700 (LWP 3668)):
#0  0x00007fce179cd12b in __lll_lock_wait_private () from /usr/lib/libc.so.6
#1  0x00007fce179cef38 in __fprintf_chk () from /usr/lib/libc.so.6
#2  0x00007fce058c72f0 in event_logv_ () from /usr/lib/libevent-2.1.so.6
#3  0x00007fce058c74b7 in event_warn () from /usr/lib/libevent-2.1.so.6
#4  0x00007fce058c8ee2 in ?? () from /usr/lib/libevent-2.1.so.6
#5  0x00007fce058beac8 in event_base_loop () from /usr/lib/libevent-2.1.so.6
#6  0x00007fce0eaffe29 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#7  0x00007fce0ea9b63b in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#8  0x00007fce0eace608 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#9  0x00007fce0eaff361 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#10 0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#11 0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 8 (Thread 0x7fcddffff700 (LWP 3658)):
#0  0x00007fce179b4c21 in poll () from /usr/lib/libc.so.6
#1  0x00007fce144b7540 in ?? () from /usr/lib/libglib-2.0.so.0
#2  0x00007fce144b762e in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#3  0x00007fce17ee75c4 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#4  0x00007fce17e9058c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#5  0x00007fce17cd45c9 in QThread::exec() () from /usr/lib/libQt5Core.so.5
#6  0x00007fce17cd59cc in ?? () from /usr/lib/libQt5Core.so.5
#7  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#8  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 7 (Thread 0x7fcdf4e10700 (LWP 3653)):
#0  0x00007fce179b4c21 in poll () from /usr/lib/libc.so.6
#1  0x00007fce144b7540 in ?? () from /usr/lib/libglib-2.0.so.0
#2  0x00007fce144b762e in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#3  0x00007fce17ee75c4 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#4  0x00007fce17e9058c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#5  0x00007fce17cd45c9 in QThread::exec() () from /usr/lib/libQt5Core.so.5
#6  0x00007fce17cd59cc in ?? () from /usr/lib/libQt5Core.so.5
#7  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#8  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 6 (Thread 0x7fcdf5611700 (LWP 3652)):
#0  0x00007fce17ee719b in ?? () from /usr/lib/libQt5Core.so.5
#1  0x00007fce144b6e0a in g_main_context_prepare () from /usr/lib/libglib-2.0.so.0
#2  0x00007fce144b7466 in ?? () from /usr/lib/libglib-2.0.so.0
#3  0x00007fce144b762e in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#4  0x00007fce17ee75c4 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#5  0x00007fce17e9058c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#6  0x00007fce17cd45c9 in QThread::exec() () from /usr/lib/libQt5Core.so.5
#7  0x00007fce17cd59cc in ?? () from /usr/lib/libQt5Core.so.5
#8  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#9  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 5 (Thread 0x7fcdf5eb2700 (LWP 3651)):
#0  0x00007fce179b4c21 in poll () from /usr/lib/libc.so.6
#1  0x00007fce144b7540 in ?? () from /usr/lib/libglib-2.0.so.0
#2  0x00007fce144b762e in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#3  0x00007fce17ee75c4 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#4  0x00007fce17e9058c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#5  0x00007fce17cd45c9 in QThread::exec() () from /usr/lib/libQt5Core.so.5
#6  0x00007fce17cd59cc in ?? () from /usr/lib/libQt5Core.so.5
#7  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#8  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 4 (Thread 0x7fcdf70c3700 (LWP 3650)):
#0  0x00007fce144653b9 in g_mutex_lock () from /usr/lib/libglib-2.0.so.0
#1  0x00007fce144b6e17 in g_main_context_prepare () from /usr/lib/libglib-2.0.so.0
#2  0x00007fce144b7466 in ?? () from /usr/lib/libglib-2.0.so.0
#3  0x00007fce144b762e in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#4  0x00007fce17ee75c4 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#5  0x00007fce17e9058c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#6  0x00007fce17cd45c9 in QThread::exec() () from /usr/lib/libQt5Core.so.5
#7  0x00007fce174a3ba6 in ?? () from /usr/lib/libQt5DBus.so.5
#8  0x00007fce17cd59cc in ?? () from /usr/lib/libQt5Core.so.5
#9  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#10 0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 3 (Thread 0x7fcdf7fff700 (LWP 3649)):
#0  0x00007fce179b4c21 in poll () from /usr/lib/libc.so.6
#1  0x00007fce14295630 in ?? () from /usr/lib/libxcb.so.1
#2  0x00007fce142972db in xcb_wait_for_event () from /usr/lib/libxcb.so.1
#3  0x00007fcdfcfa096b in ?? () from /usr/lib/libQt5XcbQpa.so.5
#4  0x00007fce17cd59cc in ?? () from /usr/lib/libQt5Core.so.5
#5  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#6  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 2 (Thread 0x7fcdfdeb4700 (LWP 3648)):
#0  0x00007fce15384e5b in pthread_cond_timedwait@@GLIBC_2.3.2 () from /usr/lib/libpthread.so.0
#1  0x00007fce14f56ea4 in ?? () from /usr/lib/nvidia/libGL.so.1
#2  0x00007fce09bca522 in ?? () from /usr/lib/nvidia/libnvidia-glcore.so.340.107
#3  0x00007fce14f56db4 in ?? () from /usr/lib/nvidia/libGL.so.1
#4  0x00007fce1537ea9d in start_thread () from /usr/lib/libpthread.so.0
#5  0x00007fce179bfb23 in clone () from /usr/lib/libc.so.6

Thread 1 (Thread 0x7fcdfdebfb40 (LWP 3647)):
[KCrash Handler]
#6  0x00007fce130015a0 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#7  0x00007fce0e43ee91 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#8  0x00007fce0e43f32f in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#9  0x00007fce0e775d2f in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#10 0x00007fce0e78431a in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#11 0x00007fce0e5a0e39 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#12 0x00007fce0e5a1001 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#13 0x00007fce0e5a7be7 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#14 0x00007fce0e5a7e01 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#15 0x00007fce0e589a51 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#16 0x00007fce0e8aca58 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#17 0x00007fce0e8ad421 in ?? () from /usr/lib/libQt5WebEngineCore.so.5
#18 0x00007fce0cf2d54c in QtWebEngineCore::WebContentsAdapter::~WebContentsAdapter() () from /usr/lib/libQt5WebEngineCore.so.5
#19 0x00007fce134588c4 in ?? () from /usr/lib/libQt5WebEngineWidgets.so.5
#20 0x00007fce13458959 in ?? () from /usr/lib/libQt5WebEngineWidgets.so.5
#21 0x00007fce134543f0 in QWebEnginePage::~QWebEnginePage() () from /usr/lib/libQt5WebEngineWidgets.so.5
#22 0x00007fce16d009ca in MessageViewer::MailWebEnginePage::~MailWebEnginePage() () from /usr/lib/libKF5MessageViewer.so.5
#23 0x00007fce17eba1cb in QObjectPrivate::deleteChildren() () from /usr/lib/libQt5Core.so.5
#24 0x00007fce1889410f in QWidget::~QWidget() () from /usr/lib/libQt5Widgets.so.5
#25 0x00007fce16cff0ba in MessageViewer::MailWebEngineView::~MailWebEngineView() () from /usr/lib/libKF5MessageViewer.so.5
#26 0x00007fce16ca6946 in ?? () from /usr/lib/libKF5MessageViewer.so.5
#27 0x00007fce16ca6b09 in ?? () from /usr/lib/libKF5MessageViewer.so.5
#28 0x00007fce17eba1cb in QObjectPrivate::deleteChildren() () from /usr/lib/libQt5Core.so.5
#29 0x00007fce1889410f in QWidget::~QWidget() () from /usr/lib/libQt5Widgets.so.5
#30 0x00007fce16c9a24a in MessageViewer::Viewer::~Viewer() () from /usr/lib/libKF5MessageViewer.so.5
#31 0x00007fce17eba1cb in QObjectPrivate::deleteChildren() () from /usr/lib/libQt5Core.so.5
#32 0x00007fce1889410f in QWidget::~QWidget() () from /usr/lib/libQt5Widgets.so.5
#33 0x00007fce18fdecea in KMReaderWin::~KMReaderWin() () from /usr/lib/libkmailprivate.so.5
#34 0x00007fce17eba1cb in QObjectPrivate::deleteChildren() () from /usr/lib/libQt5Core.so.5
#35 0x00007fce1889410f in QWidget::~QWidget() () from /usr/lib/libQt5Widgets.so.5
#36 0x00007fce189ff22a in QSplitter::~QSplitter() () from /usr/lib/libQt5Widgets.so.5
#37 0x00007fce17eba1cb in QObjectPrivate::deleteChildren() () from /usr/lib/libQt5Core.so.5
#38 0x00007fce1889410f in QWidget::~QWidget() () from /usr/lib/libQt5Widgets.so.5
#39 0x00007fce189ff22a in QSplitter::~QSplitter() () from /usr/lib/libQt5Widgets.so.5
#40 0x00007fce19017033 in KMMainWidget::deleteWidgets() () from /usr/lib/libkmailprivate.so.5
#41 0x00007fce1902fd6f in KMMainWidget::destruct() () from /usr/lib/libkmailprivate.so.5
#42 0x00007fce1902ff51 in KMMainWidget::~KMMainWidget() () from /usr/lib/libkmailprivate.so.5
#43 0x00007fce1903016a in KMMainWidget::~KMMainWidget() () from /usr/lib/libkmailprivate.so.5
#44 0x00007fce17eba1cb in QObjectPrivate::deleteChildren() () from /usr/lib/libQt5Core.so.5
#45 0x00007fce1889410f in QWidget::~QWidget() () from /usr/lib/libQt5Widgets.so.5
#46 0x00007fce177b8e35 in KMainWindow::~KMainWindow() () from /usr/lib/libKF5XmlGui.so.5
#47 0x00007fce18fda83c in KMMainWin::~KMMainWin() () from /usr/lib/libkmailprivate.so.5
#48 0x00007fce18fda8aa in KMMainWin::~KMMainWin() () from /usr/lib/libkmailprivate.so.5
#49 0x00007fce17ebcb81 in QObject::event(QEvent*) () from /usr/lib/libQt5Core.so.5
#50 0x00007fce18898e8c in QWidget::event(QEvent*) () from /usr/lib/libQt5Widgets.so.5
#51 0x00007fce189a53a5 in QMainWindow::event(QEvent*) () from /usr/lib/libQt5Widgets.so.5
#52 0x00007fce177bb3bc in KMainWindow::event(QEvent*) () from /usr/lib/libKF5XmlGui.so.5
#53 0x00007fce17806ba6 in KXmlGuiWindow::event(QEvent*) () from /usr/lib/libKF5XmlGui.so.5
#54 0x00007fce18857e34 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQt5Widgets.so.5
#55 0x00007fce1885f671 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQt5Widgets.so.5
#56 0x00007fce17e918f9 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from /usr/lib/libQt5Core.so.5
#57 0x00007fce17e94998 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from /usr/lib/libQt5Core.so.5
#58 0x00007fce17ee7fd4 in ?? () from /usr/lib/libQt5Core.so.5
#59 0x00007fce144b5a2f in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#60 0x00007fce144b75e9 in ?? () from /usr/lib/libglib-2.0.so.0
#61 0x00007fce144b762e in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#62 0x00007fce17ee75a9 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#63 0x00007fce17e9058c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#64 0x00007fce17e98896 in QCoreApplication::exec() () from /usr/lib/libQt5Core.so.5
#65 0x000055cd7b944f70 in ?? ()
#66 0x00007fce178e8223 in __libc_start_main () from /usr/lib/libc.so.6
#67 0x000055cd7b94512e in _start ()
[Inferior 1 (process 3647) detached]

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