backtrace, please.

I'm sorry.
Added below:
Application: Kate (kate), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f414c3dd780 (LWP 3894))]

Thread 4 (Thread 0x7f4137abe700 (LWP 3896)):
#0  0x00007f414bd17303 in __GI___poll (fds=<optimized out>, nfds=<optimized out>, timeout=<optimized out>) at ../sysdeps/unix/sysv/linux/poll.c:87
#1  0x00007f4148e38036 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f4148e3849a in g_main_loop_run () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f4137ac398b in ?? () from /usr/lib/x86_64-linux-gnu/gio/modules/libdconfsettings.so
#4  0x00007f4148e599e5 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f4149304e9a in start_thread (arg=0x7f4137abe700) at pthread_create.c:308
#6  0x00007f414bd22cbd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#7  0x0000000000000000 in ?? ()

Thread 3 (Thread 0x7f41372bd700 (LWP 3897)):
#0  0x00007f4148e09650 in poll@plt () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#1  0x00007f4148e38036 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f4148e3849a in g_main_loop_run () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f413ec15406 in ?? () from /usr/lib/x86_64-linux-gnu/libgio-2.0.so.0
#4  0x00007f4148e599e5 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f4149304e9a in start_thread (arg=0x7f41372bd700) at pthread_create.c:308
#6  0x00007f414bd22cbd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#7  0x0000000000000000 in ?? ()

Thread 2 (Thread 0x7f4121601700 (LWP 3901)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:162
#1  0x00007f4123669222 in ?? () from /usr/lib/x86_64-linux-gnu/libQtScript.so.4
#2  0x00007f4123669259 in ?? () from /usr/lib/x86_64-linux-gnu/libQtScript.so.4
#3  0x00007f4149304e9a in start_thread (arg=0x7f4121601700) at pthread_create.c:308
#4  0x00007f414bd22cbd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#5  0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f414c3dd780 (LWP 3894)):
[KCrash Handler]
#6  0x0000000000000050 in ?? ()
#7  0x00007f4149bdeb04 in QObject::disconnect (sender=0x247d970, signal=0x27c6489 "rowsInserted(QModelIndex,int,int)", receiver=0x247c5e0, method=0x27c5b49 "_k_slotRowsInserted(QModelIndex,int,int)") at kernel/qobject.cpp:2891
#8  0x00007f414a3b4cff in eventFilter (event=0x7fffe50739a0, watched=0x247fcb0, this=0x2479600) at ../../kdeui/itemviews/kwidgetitemdelegate.cpp:253
#9  KWidgetItemDelegatePrivate::eventFilter (this=0x2479600, watched=0x247fcb0, event=0x7fffe50739a0) at ../../kdeui/itemviews/kwidgetitemdelegate.cpp:236
#10 0x00007f4149bcb028 in QCoreApplicationPrivate::sendThroughObjectEventFilters (this=<optimized out>, receiver=0x247fcb0, event=0x7fffe50739a0) at kernel/qcoreapplication.cpp:986
#11 0x00007f414b12c85f in notify_helper (e=0x7fffe50739a0, receiver=0x247fcb0, this=0x1a5ebf0) at kernel/qapplication.cpp:4555
#12 QApplicationPrivate::notify_helper (this=0x1a5ebf0, receiver=0x247fcb0, e=0x7fffe50739a0) at kernel/qapplication.cpp:4531
#13 0x00007f414b131713 in QApplication::notify (this=0x7fffe50749e0, receiver=0x247fcb0, e=0x7fffe50739a0) at kernel/qapplication.cpp:4420
#14 0x00007f414a3d63f6 in KApplication::notify (this=0x7fffe50749e0, receiver=0x247fcb0, event=0x7fffe50739a0) at ../../kdeui/kernel/kapplication.cpp:311
#15 0x00007f4149bcae9c in QCoreApplication::notifyInternal (this=0x7fffe50749e0, receiver=0x247fcb0, event=0x7fffe50739a0) at kernel/qcoreapplication.cpp:876
#16 0x00007f414b64730d in sendEvent (event=0x7fffe50739a0, receiver=0x247fcb0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:231
#17 QAccessible::queryAccessibleInterface (object=0x247fcb0) at accessible/qaccessible.cpp:593
#18 0x00007f414b64d51d in QAccessible::updateAccessibility (o=<optimized out>, who=0, reason=QAccessible::ObjectDestroyed) at accessible/qaccessible_unix.cpp:102
#19 0x00007f414b17774f in QWidget::~QWidget (this=0x247fcb0, __in_chrg=<optimized out>) at kernel/qwidget.cpp:1679
#20 0x00007f414b177a19 in QWidget::~QWidget (this=0x247fcb0, __in_chrg=<optimized out>) at kernel/qwidget.cpp:1700
#21 0x00007f4149bdd935 in QObjectPrivate::deleteChildren (this=0x247d140) at kernel/qobject.cpp:1908
#22 0x00007f414b177740 in QWidget::~QWidget (this=0x24fa3e0, __in_chrg=<optimized out>) at kernel/qwidget.cpp:1676
#23 0x00007f414a34ef8e in ~KAboutApplicationPersonListView (this=0x24fa3e0, __in_chrg=<optimized out>) at ../../kdeui/dialogs/kaboutapplicationpersonlistview_p.h:26
#24 KDEPrivate::KAboutApplicationPersonListView::~KAboutApplicationPersonListView (this=0x24fa3e0, __in_chrg=<optimized out>) at ../../kdeui/dialogs/kaboutapplicationpersonlistview_p.h:26
#25 0x00007f4149bdd935 in QObjectPrivate::deleteChildren (this=0x247d5c0) at kernel/qobject.cpp:1908
#26 0x00007f414b177740 in QWidget::~QWidget (this=0x2472fd0, __in_chrg=<optimized out>) at kernel/qwidget.cpp:1676
#27 0x00007f414b177a19 in QWidget::~QWidget (this=0x2472fd0, __in_chrg=<optimized out>) at kernel/qwidget.cpp:1700
#28 0x00007f4149bdd935 in QObjectPrivate::deleteChildren (this=0x24fa040) at kernel/qobject.cpp:1908
#29 0x00007f414b177740 in QWidget::~QWidget (this=0x24fa010, __in_chrg=<optimized out>) at kernel/qwidget.cpp:1676
#30 0x00007f414b5984b9 in QStackedWidget::~QStackedWidget (this=0x24fa010, __in_chrg=<optimized out>) at widgets/qstackedwidget.cpp:193
#31 0x00007f4149bdd935 in QObjectPrivate::deleteChildren (this=0x24f9dd0) at kernel/qobject.cpp:1908
#32 0x00007f414b177740 in QWidget::~QWidget (this=0x23c5e90, __in_chrg=<optimized out>) at kernel/qwidget.cpp:1676
#33 0x00007f414b5a3fa9 in QTabWidget::~QTabWidget (this=0x23c5e90, __in_chrg=<optimized out>) at widgets/qtabwidget.cpp:367
#34 0x00007f4149bdd935 in QObjectPrivate::deleteChildren (this=0x2478840) at kernel/qobject.cpp:1908
#35 0x00007f414b177740 in QWidget::~QWidget (this=0x2478810, __in_chrg=<optimized out>) at kernel/qwidget.cpp:1676
#36 0x00007f414b177a19 in QWidget::~QWidget (this=0x2478810, __in_chrg=<optimized out>) at kernel/qwidget.cpp:1700
#37 0x00007f4149bdd935 in QObjectPrivate::deleteChildren (this=0x24f0590) at kernel/qobject.cpp:1908
#38 0x00007f414b177740 in QWidget::~QWidget (this=0x20b4550, __in_chrg=<optimized out>) at kernel/qwidget.cpp:1676
#39 0x00007f414a342729 in KAboutApplicationDialog::~KAboutApplicationDialog (this=0x20b4550, __in_chrg=<optimized out>) at ../../kdeui/dialogs/kaboutapplicationdialog.cpp:306
#40 0x00007f414a4813be in KHelpMenu::timerExpired (this=0x1f145a0) at ../../kdeui/widgets/khelpmenu.cpp:373
#41 0x00007f4149be4446 in QObject::event (this=0x1f145a0, e=<optimized out>) at kernel/qobject.cpp:1195
#42 0x00007f414b12c894 in notify_helper (e=0x27cf6c0, receiver=0x1f145a0, this=0x1a5ebf0) at kernel/qapplication.cpp:4559
#43 QApplicationPrivate::notify_helper (this=0x1a5ebf0, receiver=0x1f145a0, e=0x27cf6c0) at kernel/qapplication.cpp:4531
#44 0x00007f414b131713 in QApplication::notify (this=0x7fffe50749e0, receiver=0x1f145a0, e=0x27cf6c0) at kernel/qapplication.cpp:4420
#45 0x00007f414a3d63f6 in KApplication::notify (this=0x7fffe50749e0, receiver=0x1f145a0, event=0x27cf6c0) at ../../kdeui/kernel/kapplication.cpp:311
#46 0x00007f4149bcae9c in QCoreApplication::notifyInternal (this=0x7fffe50749e0, receiver=0x1f145a0, event=0x27cf6c0) at kernel/qcoreapplication.cpp:876
#47 0x00007f4149bcec6a in sendEvent (event=0x27cf6c0, receiver=0x1f145a0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:231
#48 QCoreApplicationPrivate::sendPostedEvents (receiver=0x0, event_type=0, data=0x1a25670) at kernel/qcoreapplication.cpp:1500
#49 0x00007f4149bf9f93 in sendPostedEvents () at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:236
#50 postEventSourceDispatch (s=<optimized out>) at kernel/qeventdispatcher_glib.cpp:279
#51 0x00007f4148e37d53 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#52 0x00007f4148e380a0 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#53 0x00007f4148e38164 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#54 0x00007f4149bfa3bf in QEventDispatcherGlib::processEvents (this=0x1a26b30, flags=...) at kernel/qeventdispatcher_glib.cpp:424
#55 0x00007f414b1d4d5e in QGuiEventDispatcherGlib::processEvents (this=<optimized out>, flags=...) at kernel/qguieventdispatcher_glib.cpp:204
#56 0x00007f4149bc9c82 in QEventLoop::processEvents (this=<optimized out>, flags=...) at kernel/qeventloop.cpp:149
#57 0x00007f4149bc9ed7 in QEventLoop::exec (this=0x7fffe5074920, flags=...) at kernel/qeventloop.cpp:204
#58 0x00007f4149bcef67 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1148
#59 0x00007f414bff40d5 in kdemain (argc=<optimized out>, argv=<optimized out>) at ../../../kate/app/katemain.cpp:377
#60 0x00007f414bc5076d in __libc_start_main (main=0x400630 <main(int, char**)>, argc=2, ubp_av=0x7fffe5075f18, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffe5075f08) at libc-start.c:226
#61 0x0000000000400661 in _start ()

Thanks for your feedback.

Should be fixed with Qt 4.8.1. Which version of Qt do you use? What KDE version?

*** This bug has been marked as a duplicate of bug 305931 ***