SUMMARY

Everything is going nice, your desktop and applications keep running smoothly while you're editing a "LibreOffice Draw" document when you suddenly realize that you no longer have panels and your desktop background is now a black hole, not letting any information out! However "kwin" and the usual keyboard shortcuts are still there! 

So I call "yakuake". Here is what I get as output of command `ps axu | grep plasma`:

   `6535 ? S 0:00 file.so [kdeinit5] file local:/run/user/1000/klauncherTJ1322.1.slave-socket local:/run/user/1000/plasmashellHf6516.2.slave-socket` 

Next I `kill -9 6535` to pass the whole process and restart "plasma" using `plasmashell -n` with poor results. Happiness lasts a second...

Now the "Crashing Reporting Assitant" comming out into our aid and the rest of history is already known... Their «hair and signals» are bellow

greetings!


Application: Plasma (plasmashell), signal: Aborted
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f482561dd80 (LWP 7143))]

Thread 14 (Thread 0x7f47396e9700 (LWP 7163)):
#0  0x00007f481ebeb064 in __GI___libc_read (fd=36, buf=0x7f47396e8b50, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:27
#1  0x00007f481979c4c0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f48197571d7 in g_main_context_check () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f4819757690 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f48197577fc in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f481f53887b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f481f4dd8da in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f481f2fc23a in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f473bdc7747 in KCupsConnection::run() () at /usr/lib/x86_64-linux-gnu/libkcupslib.so
#9  0x00007f481f30117d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#10 0x00007f481e4826db in start_thread (arg=0x7f47396e9700) at pthread_create.c:463
#11 0x00007f481ebfc61f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 13 (Thread 0x7f474303d700 (LWP 7159)):
#0  0x00007f481e488ad3 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f474ecd21b8 <Qalculate::instance()::inst+472>) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f481e488ad3 in __pthread_cond_wait_common (abstime=0x0, mutex=0x7f474ecd2168 <Qalculate::instance()::inst+392>, cond=0x7f474ecd2190 <Qalculate::instance()::inst+432>) at pthread_cond_wait.c:502
#2  0x00007f481e488ad3 in __pthread_cond_wait (cond=0x7f474ecd2190 <Qalculate::instance()::inst+432>, mutex=0x7f474ecd2168 <Qalculate::instance()::inst+392>) at pthread_cond_wait.c:655
#3  0x00007f481ef838bc in std::condition_variable::wait(std::unique_lock<std::mutex>&) () at /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#4  0x00007f474eab0984 in Qalculate::worker() () at /usr/lib/x86_64-linux-gnu/qt5/qml/org/kde/private/qalculate/libplasmoidplugin.so
#5  0x00007f481ef896df in  () at /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#6  0x00007f481e4826db in start_thread (arg=0x7f474303d700) at pthread_create.c:463
#7  0x00007f481ebfc61f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 12 (Thread 0x7f4743edc700 (LWP 7158)):
#0  0x00007f481ebeb064 in __GI___libc_read (fd=32, buf=0x7f4743edbb90, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:27
#1  0x00007f481979c4c0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f48197571d7 in g_main_context_check () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f4819757690 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f48197577fc in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f481f53887b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f481f4dd8da in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f481f2fc23a in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f481f30117d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f481e4826db in start_thread (arg=0x7f4743edc700) at pthread_create.c:463
#10 0x00007f481ebfc61f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 11 (Thread 0x7f4754c7c700 (LWP 7153)):
#0  0x00007f481ebeb064 in __GI___libc_read (fd=22, buf=0x7f4754c7bb20, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:27
#1  0x00007f481979c4c0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f48197571d7 in g_main_context_check () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f4819757690 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f48197577fc in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f481f53887b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f481f4dd8da in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f481f2fc23a in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f48230082a6 in  () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#9  0x00007f481f30117d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#10 0x00007f481e4826db in start_thread (arg=0x7f4754c7c700) at pthread_create.c:463
#11 0x00007f481ebfc61f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 10 (Thread 0x7f477164a700 (LWP 7152)):
#0  0x00007f481e488ad3 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x55b6f8c437bc) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f481e488ad3 in __pthread_cond_wait_common (abstime=0x0, mutex=0x55b6f8c43768, cond=0x55b6f8c43790) at pthread_cond_wait.c:502
#2  0x00007f481e488ad3 in __pthread_cond_wait (cond=0x55b6f8c43790, mutex=0x55b6f8c43768) at pthread_cond_wait.c:655
#3  0x00007f47735689ab in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#4  0x00007f4773568597 in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#5  0x00007f481e4826db in start_thread (arg=0x7f477164a700) at pthread_create.c:463
#6  0x00007f481ebfc61f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 9 (Thread 0x7f4771e4b700 (LWP 7151)):
#0  0x00007f481e488ad3 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x55b6f8c437bc) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f481e488ad3 in __pthread_cond_wait_common (abstime=0x0, mutex=0x55b6f8c43768, cond=0x55b6f8c43790) at pthread_cond_wait.c:502
#2  0x00007f481e488ad3 in __pthread_cond_wait (cond=0x55b6f8c43790, mutex=0x55b6f8c43768) at pthread_cond_wait.c:655
#3  0x00007f47735689ab in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#4  0x00007f4773568597 in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#5  0x00007f481e4826db in start_thread (arg=0x7f4771e4b700) at pthread_create.c:463
#6  0x00007f481ebfc61f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 8 (Thread 0x7f477264c700 (LWP 7150)):
#0  0x00007f481e488ad3 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x55b6f8c437b8) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f481e488ad3 in __pthread_cond_wait_common (abstime=0x0, mutex=0x55b6f8c43768, cond=0x55b6f8c43790) at pthread_cond_wait.c:502
#2  0x00007f481e488ad3 in __pthread_cond_wait (cond=0x55b6f8c43790, mutex=0x55b6f8c43768) at pthread_cond_wait.c:655
#3  0x00007f47735689ab in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#4  0x00007f4773568597 in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#5  0x00007f481e4826db in start_thread (arg=0x7f477264c700) at pthread_create.c:463
#6  0x00007f481ebfc61f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 7 (Thread 0x7f4772e4d700 (LWP 7149)):
#0  0x00007f481e488ad3 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x55b6f8c437b8) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f481e488ad3 in __pthread_cond_wait_common (abstime=0x0, mutex=0x55b6f8c43768, cond=0x55b6f8c43790) at pthread_cond_wait.c:502
#2  0x00007f481e488ad3 in __pthread_cond_wait (cond=0x55b6f8c43790, mutex=0x55b6f8c43768) at pthread_cond_wait.c:655
#3  0x00007f47735689ab in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#4  0x00007f4773568597 in  () at /usr/lib/x86_64-linux-gnu/dri/i965_dri.so
#5  0x00007f481e4826db in start_thread (arg=0x7f4772e4d700) at pthread_create.c:463
#6  0x00007f481ebfc61f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 6 (Thread 0x7f47fa789700 (LWP 7148)):
#0  0x00007f481e488ad3 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x7f4824fddfb8) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007f481e488ad3 in __pthread_cond_wait_common (abstime=0x0, mutex=0x7f4824fddf68, cond=0x7f4824fddf90) at pthread_cond_wait.c:502
#2  0x00007f481e488ad3 in __pthread_cond_wait (cond=0x7f4824fddf90, mutex=0x7f4824fddf68) at pthread_cond_wait.c:655
#3  0x00007f4824ce75f4 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#4  0x00007f4824ce7639 in  () at /usr/lib/x86_64-linux-gnu/libQt5Script.so.5
#5  0x00007f481e4826db in start_thread (arg=0x7f47fa789700) at pthread_create.c:463
#6  0x00007f481ebfc61f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 5 (Thread 0x7f4804d50700 (LWP 7147)):
#0  0x00007f481ebeb064 in __GI___libc_read (fd=13, buf=0x7f4804d4fb70, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:27
#1  0x00007f481979c4c0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f48197571d7 in g_main_context_check () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f4819757690 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f48197577fc in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f481f53887b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f481f4dd8da in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f481f2fc23a in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f482246e6f5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#9  0x00007f481f30117d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#10 0x00007f481e4826db in start_thread (arg=0x7f4804d50700) at pthread_create.c:463
#11 0x00007f481ebfc61f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7f4806dbb700 (LWP 7146)):
#0  0x00007f481979d839 in g_mutex_lock () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#1  0x00007f48197575f0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f48197577fc in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f481f53887b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007f481f4dd8da in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f481f2fc23a in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f482246e6f5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#7  0x00007f481f30117d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f481e4826db in start_thread (arg=0x7f4806dbb700) at pthread_create.c:463
#9  0x00007f481ebfc61f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7f480c969700 (LWP 7145)):
#0  0x00007f481ebeb064 in __GI___libc_read (fd=7, buf=0x7f480c968b60, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:27
#1  0x00007f481979c4c0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f48197571d7 in g_main_context_check () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f4819757690 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f48197577fc in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f481f53887b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007f481f4dd8da in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007f481f2fc23a in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007f481f9b5d45 in  () at /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#9  0x00007f481f30117d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#10 0x00007f481e4826db in start_thread (arg=0x7f480c969700) at pthread_create.c:463
#11 0x00007f481ebfc61f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7f480eef6700 (LWP 7144)):
#0  0x00007f481ebefbb9 in __GI___poll (fds=0x7f480eef5ca8, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f4823c14747 in  () at /usr/lib/x86_64-linux-gnu/libxcb.so.1
#2  0x00007f4823c1636a in xcb_wait_for_event () at /usr/lib/x86_64-linux-gnu/libxcb.so.1
#3  0x00007f481188f5e9 in  () at /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#4  0x00007f481f30117d in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007f481e4826db in start_thread (arg=0x7f480eef6700) at pthread_create.c:463
#6  0x00007f481ebfc61f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7f482561dd80 (LWP 7143)):
[KCrash Handler]
#6  0x00007f481eb19e87 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51
#7  0x00007f481eb1b7f1 in __GI_abort () at abort.c:79
#8  0x00007f481eb64837 in __libc_message (action=action@entry=do_abort, fmt=fmt@entry=0x7f481ec91a7b "%s\n") at ../sysdeps/posix/libc_fatal.c:181
#9  0x00007f481eb6b8ba in malloc_printerr (str=str@entry=0x7f481ec8fc76 "free(): invalid pointer") at malloc.c:5342
#10 0x00007f481eb72dec in _int_free (have_lock=0, p=0x55b6fa5c69d8, av=0x7f481eec6c40 <main_arena>) at malloc.c:4167
#11 0x00007f481eb72dec in __GI___libc_free (mem=0x55b6fa5c69e8) at malloc.c:3134
#12 0x00007f481f50f0b0 in QObject::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#13 0x00007f48204e783c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#14 0x00007f48204ef104 in QApplication::notify(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#15 0x00007f481f4df8a8 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#16 0x00007f481f4e201d in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#17 0x00007f481f539233 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#18 0x00007f4819757537 in g_main_context_dispatch () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#19 0x00007f4819757770 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#20 0x00007f48197577fc in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#21 0x00007f481f53885f in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#22 0x00007f481f4dd8da in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#23 0x00007f481f4e6984 in QCoreApplication::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#24 0x000055b6f6a30d6a in  ()
#25 0x00007f481eafcc87 in __libc_start_main (main=0x55b6f6a30390, argc=2, argv=0x7ffe346d56f8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffe346d56e8) at ../csu/libc-start.c:310
#26 0x000055b6f6a3110a in _start ()


STEPS TO REPRODUCE
described above


SOFTWARE/OS VERSIONS

Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 5.12.9
KDE Frameworks Version: 5.44.0
Qt Version: 5.9.5