When using kmail with german language as default installed and selecting "Aktion suchen ..." (search for action) in the help menu and pressing any key, kmail crashes . (I needed to configure a IMAP account in order to reproduce with a plain debian testing install) . Without configuring that account kmail didn't crash. Using C or American English kmail does not crash. This is the backtrace Application: KMail (kmail), signal: Segmentation fault [KCrash Handler] #4 0x00007f5cf935c87c in QAction::text() const () at /lib/x86_64-linux- gnu/libQt5Widgets.so.5 #5 0x00007f5cf62dac49 in ??? () at /lib/x86_64-linux- gnu/libKF5ConfigWidgets.so.5 #6 0x00007f5cf62dbb10 in ??? () at /lib/x86_64-linux- gnu/libKF5ConfigWidgets.so.5 #7 0x00007f5cf62cf524 in ??? () at /lib/x86_64-linux- gnu/libKF5ConfigWidgets.so.5 #8 0x00007f5cf86a99ce in ??? () at /lib/x86_64-linux-gnu/libQt5Core.so.5 #9 0x00007f5cf86ae04b in QSortFilterProxyModel::columnCount(QModelIndex const&) const () at /lib/x86_64-linux-gnu/libQt5Core.so.5 #10 0x00007f5cf95fc2cf in QHeaderView::initializeSections() () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #11 0x00007f5cf960120e in QHeaderView::reset() () at /lib/x86_64-linux- gnu/libQt5Widgets.so.5 #12 0x00007f5cf8718c92 in ??? () at /lib/x86_64-linux-gnu/libQt5Core.so.5 #13 0x00007f5cf86736c1 in QAbstractItemModel::modelReset(QAbstractItemModel::QPrivateSignal) () at /lib/x86_64-linux-gnu/libQt5Core.so.5 #14 0x00007f5cf8718cbe in ??? () at /lib/x86_64-linux-gnu/libQt5Core.so.5 #15 0x00007f5cf94afe86 in QLineEdit::textChanged(QString const&) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #16 0x00007f5cf8718c92 in ??? () at /lib/x86_64-linux-gnu/libQt5Core.so.5 #17 0x00007f5cf94b7759 in QWidgetLineControl::textChanged(QString const&) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #18 0x00007f5cf94bae70 in QWidgetLineControl::finishChange(int, bool, bool) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #19 0x00007f5cf94be81e in QWidgetLineControl::processKeyEvent(QKeyEvent*) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #20 0x00007f5cf94b0073 in QLineEdit::keyPressEvent(QKeyEvent*) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #21 0x00007f5cf93a6c22 in QWidget::event(QEvent*) () at /lib/x86_64-linux- gnu/libQt5Widgets.so.5 #22 0x00007f5cf9363092 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #23 0x00007f5cf936abaf in QApplication::notify(QObject*, QEvent*) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #24 0x00007f5cf86de398 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /lib/x86_64-linux-gnu/libQt5Core.so.5 #25 0x00007f5cf93c32da in ??? () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #26 0x00007f5cf9363092 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #27 0x00007f5cf86de398 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /lib/x86_64-linux-gnu/libQt5Core.so.5 #28 0x00007f5cf8b4093d in QGuiApplicationPrivate::processKeyEvent(QWindowSystemInterfacePrivate::KeyEvent*) () at /lib/x86_64-linux-gnu/libQt5Gui.so.5 #29 0x00007f5cf8b166fc in QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Gui.so.5 #30 0x00007f5cf1ff3de4 in ??? () at /lib/x86_64-linux- gnu/libQt5WaylandClient.so.5 #31 0x00007f5cf3dd37df in ??? () at /lib/x86_64-linux-gnu/libglib-2.0.so.0 #32 0x00007f5cf3dd5a17 in ??? () at /lib/x86_64-linux-gnu/libglib-2.0.so.0 #33 0x00007f5cf3dd6180 in g_main_context_iteration () at /lib/x86_64-linux- gnu/libglib-2.0.so.0 #34 0x00007f5cf873b1ed in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5 #35 0x00007f5cf86dcd02 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5 #36 0x00007f5cf94f1fe1 in ??? () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #37 0x00007f5cf94f2100 in QMenu::exec(QPoint const&, QAction*) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #38 0x00007f5cf94f2170 in QMenu::exec() () at /lib/x86_64-linux- gnu/libQt5Widgets.so.5 #39 0x00007f5cf91c9024 in ??? () at /lib/x86_64-linux-gnu/libKF5XmlGui.so.5 #40 0x00007f5cf8718cbe in ??? () at /lib/x86_64-linux-gnu/libQt5Core.so.5 #41 0x00007f5cf935be76 in QAction::triggered(bool) () at /lib/x86_64-linux- gnu/libQt5Widgets.so.5 #42 0x00007f5cf935eb80 in QAction::activate(QAction::ActionEvent) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #43 0x00007f5cf94ec772 in ??? () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #44 0x00007f5cf94f4743 in ??? () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #45 0x00007f5cf93a5eb8 in QWidget::event(QEvent*) () at /lib/x86_64-linux- gnu/libQt5Widgets.so.5 #46 0x00007f5cf9363092 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #47 0x00007f5cf936b3ba in QApplication::notify(QObject*, QEvent*) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #48 0x00007f5cf86de398 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /lib/x86_64-linux-gnu/libQt5Core.so.5 #49 0x00007f5cf9369442 in QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool, bool) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #50 0x00007f5cf93c057d in ??? () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #51 0x00007f5cf93c328f in ??? () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #52 0x00007f5cf9363092 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () at /lib/x86_64-linux-gnu/libQt5Widgets.so.5 #53 0x00007f5cf86de398 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () at /lib/x86_64-linux-gnu/libQt5Core.so.5 #54 0x00007f5cf8b44c63 in QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::MouseEvent*) () at /lib/x86_64-linux-gnu/libQt5Gui.so.5 #55 0x00007f5cf8b166fc in QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Gui.so.5 #56 0x00007f5cf1ff3de4 in ??? () at /lib/x86_64-linux- gnu/libQt5WaylandClient.so.5 #57 0x00007f5cf3dd37df in ??? () at /lib/x86_64-linux-gnu/libglib-2.0.so.0 #58 0x00007f5cf3dd5a17 in ??? () at /lib/x86_64-linux-gnu/libglib-2.0.so.0 #59 0x00007f5cf3dd6180 in g_main_context_iteration () at /lib/x86_64-linux- gnu/libglib-2.0.so.0 #60 0x00007f5cf873b1ed in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5 #61 0x00007f5cf86dcd02 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () at /lib/x86_64-linux-gnu/libQt5Core.so.5 #62 0x00007f5cf86e5722 in QCoreApplication::exec() () at /lib/x86_64-linux- gnu/libQt5Core.so.5 #63 0x000055b1d3dccc8e in ??? () #64 0x00007f5cf7e3edba in __libc_start_call_main (main=main@entry=0x55b1d3dcbb50, argc=argc@entry=3, argv=argv@entry=0x7ffd2f4fe378) at ../sysdeps/nptl/libc_start_call_main.h:58 #65 0x00007f5cf7e3ee75 in __libc_start_main_impl (main=0x55b1d3dcbb50, argc=3, argv=0x7ffd2f4fe378, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffd2f4fe368) at ../csu/libc-start.c:360 #66 0x000055b1d3dcd391 in ??? () [Inferior 1 (process 23846) detached]