Adding a system load viewer in compact mode to the panel causes Plasma to freeze after a while. Can't reproduce in the default bar mode. 

Backtrace:
(gdb) bt
#0  0x00007ffff5ac7c18 in QQuickShaderEffectSource::updatePaintNode(QSGNode*, QQuickItem::UpdatePaintNodeData*) () from /usr/lib/libQt5Quick.so.5
#1  0x00007ffff59de408 in QQuickWindowPrivate::updateDirtyNode(QQuickItem*) () from /usr/lib/libQt5Quick.so.5
#2  0x00007ffff59dec8b in QQuickWindowPrivate::updateDirtyNodes() () from /usr/lib/libQt5Quick.so.5
#3  0x00007ffff59dee00 in QQuickWindowPrivate::syncSceneGraph() () from /usr/lib/libQt5Quick.so.5
#4  0x00007ffff59adb5c in ?? () from /usr/lib/libQt5Quick.so.5
#5  0x00007ffff59aecd1 in ?? () from /usr/lib/libQt5Quick.so.5
#6  0x00007ffff34e100c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQt5Widgets.so.5
#7  0x00007ffff34e64e6 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQt5Widgets.so.5
#8  0x00007ffff211289b in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQt5Core.so.5
#9  0x00007ffff216805d in QTimerInfoList::activateTimers() () from /usr/lib/libQt5Core.so.5
#10 0x00007ffff2168561 in ?? () from /usr/lib/libQt5Core.so.5
#11 0x00007fffedad09fd in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#12 0x00007fffedad0ce0 in ?? () from /usr/lib/libglib-2.0.so.0
#13 0x00007fffedad0d8c in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#14 0x00007ffff216923f in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#15 0x00007ffff211026a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQt5Core.so.5
#16 0x00007ffff211820c in QCoreApplication::exec() () from /usr/lib/libQt5Core.so.5
#17 0x000000000042ed66 in main ()


Reproducible: Always