Application: plasma-discover (5.14.5)

Qt Version: 5.11.2
Frameworks Version: 5.53.0
Operating System: Linux 4.15.0-43-generic x86_64
Distribution: KDE neon User Edition 5.14

-- Information about the crash:
- What I was doing when the application crashed:  Initially noticed trying to update the system.  I tried launching Discover from the menu, then from the command line.  Every time, Discover crashes just after it starts.  Terminal output is as follows:

johnny@razorback ~ $ plasma-discover
file:///usr/lib/x86_64-linux-gnu/qt5/qml/QtQuick/Controls.2/org.kde.desktop/TextField.qml:57:21: Unable to assign [undefined] to QQmlComponent*
invalid kns backend! "/etc/xdg/ksysguard.knsrc" because: "Config group not found! Check your KNS3 installation."
invalid kns backend! "/etc/xdg/servicemenu.knsrc" because: "Config group not found! Check your KNS3 installation."
adding empty sources model QStandardItemModel(0x556f2995bc80)
Could not open the AppStream metadata pool "Some components are invalid. See debug output for details"
no packages for "evince-comicsdocument"
no packages for "org.kde.plasma.systemloadviewer"
no packages for "cockpit.desktop"
no packages for "org.kde.plasma.showActivityManager"
no packages for "evince-psdocument"
no packages for "org.kde.plasma.grouping"
no packages for "evince-dvidocument"
no packages for "org.kde.plasma.diskquota"
no packages for "org.kde.kscreen"
no packages for "evince-xpsdocument"
no packages for "evince-pdfocument"
no packages for "evince-tiffdocument"
no packages for "evince-djvudocument"
no packages for "org.kde.plasma.kimpanel"
no packages for "org.kde.plasma.timer"
no packages for "im.riot.webapp"
no packages for "org.kde.plasma.appmenu"
no packages for "org.kde.plasma.quicklaunch"
org.kde.plasma.libdiscover: Couldn't find a category for  "fwupd-backend"
qml: message: Please make sure that Appstream is properly set up on your system
QObject::connect: invalid null parameter
remote hasn't changed: lvfs
KCrash: crashing... crashRecursionCounter = 2
KCrash: Application Name = plasma-discover path = /usr/bin pid = 30568
KCrash: Arguments: /usr/bin/plasma-discover 
KCrash: Attempting to start /usr/lib/x86_64-linux-gnu/libexec/drkonqi from kdeinit
sock_file=/run/user/1000/kdeinit5__0
QSocketNotifier: Invalid socket 27 and type 'Read', disabling...
QSocketNotifier: Invalid socket 30 and type 'Write', disabling...
QSocketNotifier: Invalid socket 65 and type 'Read', disabling...
QSocketNotifier: Invalid socket 40 and type 'Read', disabling...
QSocketNotifier: Invalid socket 68 and type 'Write', disabling...
QSocketNotifier: Invalid socket 50 and type 'Read', disabling...
QSocketNotifier: Invalid socket 47 and type 'Read', disabling...
QSocketNotifier: Invalid socket 51 and type 'Read', disabling...
QSocketNotifier: Invalid socket 8 and type 'Read', disabling...
QSocketNotifier: Invalid socket 26 and type 'Read', disabling...
QSocketNotifier: Invalid socket 22 and type 'Read', disabling...

[1]+  Stopped                 plasma-discover
johnny@razorback ~ $ QSocketNotifier: Invalid socket 4 and type 'Write', disabling...

------ end of terminal output.

This happens every time I try to use Discover.

The crash can be reproduced every time.

-- Backtrace:
Application: Discover (plasma-discover), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7fb2dd659200 (LWP 29388))]

Thread 11 (Thread 0x7fb27bfff700 (LWP 29405)):
#0  0x00007fb2d52d89f3 in futex_wait_cancelable (private=<optimized out>, expected=0, futex_word=0x563051dd01d4) at ../sysdeps/unix/sysv/linux/futex-internal.h:88
#1  0x00007fb2d52d89f3 in __pthread_cond_wait_common (abstime=0x0, mutex=0x563051dd0180, cond=0x563051dd01a8) at pthread_cond_wait.c:502
#2  0x00007fb2d52d89f3 in __pthread_cond_wait (cond=0x563051dd01a8, mutex=0x563051dd0180) at pthread_cond_wait.c:655
#3  0x00007fb2d92e294b in QWaitCondition::wait(QMutex*, unsigned long) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fb2dc963b18 in  () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#5  0x00007fb2dc963f4a in  () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#6  0x00007fb2d92e1adb in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fb2d52d26db in start_thread (arg=0x7fb27bfff700) at pthread_create.c:463
#8  0x00007fb2d8bd988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 10 (Thread 0x7fb292699700 (LWP 29401)):
#0  0x00007fb2d8bc80b4 in __GI___libc_read (fd=49, buf=0x7fb292698b90, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:27
#1  0x00007fb2d317bcd0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fb2d3137027 in g_main_context_check () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fb2d31374e0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007fb2d313764c in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007fb2d950704b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007fb2d94ab30a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fb2d92d6bba in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007fb2d92e1adb in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007fb2d52d26db in start_thread (arg=0x7fb292699700) at pthread_create.c:463
#10 0x00007fb2d8bd988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 9 (Thread 0x7fb29363c700 (LWP 29398)):
#0  0x00007fb2d8bc80b4 in __GI___libc_read (fd=43, buf=0x7fb29363bcd0, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:27
#1  0x00007fb2d317bcd0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fb2d3137027 in g_main_context_check () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fb2d31374e0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007fb2d31378d2 in g_main_loop_run () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007fb2a4af6026 in  () at /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#6  0x00007fb2d315f105 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#7  0x00007fb2d52d26db in start_thread (arg=0x7fb29363c700) at pthread_create.c:463
#8  0x00007fb2d8bd988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 8 (Thread 0x7fb293e3d700 (LWP 29397)):
#0  0x00007fb2d8bccbf9 in __GI___poll (fds=0x563053e9ced0, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fb2d3137539 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fb2d313764c in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fb2d3137691 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007fb2d315f105 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007fb2d52d26db in start_thread (arg=0x7fb293e3d700) at pthread_create.c:463
#6  0x00007fb2d8bd988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 7 (Thread 0x7fb2a6d01700 (LWP 29394)):
#0  0x00007fb2d8bccbf9 in __GI___poll (fds=0x7fb29803ff90, nfds=3, timeout=134715) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fb2d3137539 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fb2d313764c in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fb2d950704b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fb2d94ab30a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fb2d92d6bba in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007fb2d92e1adb in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fb2d52d26db in start_thread (arg=0x7fb2a6d01700) at pthread_create.c:463
#8  0x00007fb2d8bd988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 6 (Thread 0x7fb2a8282700 (LWP 29393)):
#0  0x00007fb2d8bccbf9 in __GI___poll (fds=0x7fb2a0004e10, nfds=1, timeout=9715) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fb2d3137539 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fb2d313764c in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fb2d950704b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fb2d94ab30a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fb2d92d6bba in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007fb2d92e1adb in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fb2d52d26db in start_thread (arg=0x7fb2a8282700) at pthread_create.c:463
#8  0x00007fb2d8bd988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 5 (Thread 0x7fb2b17e7700 (LWP 29392)):
#0  0x00007fb2d317d049 in g_mutex_lock () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#1  0x00007fb2d31363e0 in g_main_context_acquire () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fb2d31373f5 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fb2d313764c in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007fb2d950704b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fb2d94ab30a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007fb2d92d6bba in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fb2dc8e4826 in  () at /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#8  0x00007fb2d92e1adb in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007fb2d52d26db in start_thread (arg=0x7fb2b17e7700) at pthread_create.c:463
#10 0x00007fb2d8bd988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 4 (Thread 0x7fb2c12c2700 (LWP 29391)):
#0  0x00007fb2d8bccbf9 in __GI___poll (fds=0x7fb2b4004a00, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fb2d3137539 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fb2d313764c in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fb2d950704b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4  0x00007fb2d94ab30a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fb2d92d6bba in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007fb2d9e7d4f5 in  () at /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#7  0x00007fb2d92e1adb in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007fb2d52d26db in start_thread (arg=0x7fb2c12c2700) at pthread_create.c:463
#9  0x00007fb2d8bd988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 3 (Thread 0x7fb2c24d3700 (LWP 29390)):
#0  0x00007fb2d8bc80b4 in __GI___libc_read (fd=7, buf=0x7fb2c24d2b60, nbytes=16) at ../sysdeps/unix/sysv/linux/read.c:27
#1  0x00007fb2d317bcd0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007fb2d3137027 in g_main_context_check () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007fb2d31374e0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007fb2d313764c in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007fb2d950704b in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007fb2d94ab30a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007fb2d92d6bba in QThread::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007fb2db1d7e45 in  () at /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#9  0x00007fb2d92e1adb in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#10 0x00007fb2d52d26db in start_thread (arg=0x7fb2c24d3700) at pthread_create.c:463
#11 0x00007fb2d8bd988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 2 (Thread 0x7fb2cabf5700 (LWP 29389)):
#0  0x00007fb2d8bccbf9 in __GI___poll (fds=0x7fb2cabf4ca8, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007fb2d286b747 in  () at /usr/lib/x86_64-linux-gnu/libxcb.so.1
#2  0x00007fb2d286d36a in xcb_wait_for_event () at /usr/lib/x86_64-linux-gnu/libxcb.so.1
#3  0x00007fb2cdbb5ed9 in  () at /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#4  0x00007fb2d92e1adb in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007fb2d52d26db in start_thread (arg=0x7fb2cabf5700) at pthread_create.c:463
#6  0x00007fb2d8bd988f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Thread 1 (Thread 0x7fb2dd659200 (LWP 29388)):
[KCrash Handler]
#6  0x00007fb2dc57dd62 in AbstractResource::reportNewState() () at /usr/lib/x86_64-linux-gnu/plasma-discover/libDiscoverCommon.so
#7  0x00007fb2d94dc18f in QMetaObject::activate(QObject*, int, int, void**) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007fb294068cb5 in  () at /usr/lib/x86_64-linux-gnu/qt5/plugins/discover/fwupd-backend.so
#9  0x00007fb2940694e7 in  () at /usr/lib/x86_64-linux-gnu/qt5/plugins/discover/fwupd-backend.so
#10 0x00007fb294069dc1 in  () at /usr/lib/x86_64-linux-gnu/qt5/plugins/discover/fwupd-backend.so
#11 0x00007fb2d94dc18f in QMetaObject::activate(QObject*, int, int, void**) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#12 0x00007fb2d92df223 in QFutureWatcherBase::event(QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#13 0x00007fb2daac7e1c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#14 0x00007fb2daacf3ef in QApplication::notify(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#15 0x00007fb2d94acfe8 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#16 0x00007fb2d94afb2d in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#17 0x00007fb2d95079f3 in  () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#18 0x00007fb2d3137387 in g_main_context_dispatch () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#19 0x00007fb2d31375c0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#20 0x00007fb2d313764c in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#21 0x00007fb2d950702f in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#22 0x00007fb2cdc41761 in  () at /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5
#23 0x00007fb2d94ab30a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#24 0x00007fb2d94b44d0 in QCoreApplication::exec() () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#25 0x000056305009d868 in  ()
#26 0x00007fb2d8ad9b97 in __libc_start_main (main=0x56305009cf90, argc=3, argv=0x7ffe82a1ed58, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffe82a1ed48) at ../csu/libc-start.c:310
#27 0x000056305009daea in _start ()

Reported using DrKonqi