Application: systemsettings5 (5.2.2)

Qt Version: 5.4.1
Operating System: Linux 3.19.0-26-generic x86_64
Distribution: Ubuntu 15.04

-- Information about the crash:
Impostazioni di Sistema si è chiuso durante il cambio del tema delle finestre delle applicazioni
Ho installato altri temi per la visualizzazione delle finestre quando ho cercato di impostarne uno "Impostazioni di Sistema" ha creshato e si è chiuso.
Ora non riesco più ad entrare per cambiare il tema delle finestre.

The crash can be reproduced every time.

-- Backtrace:
Application: Impostazioni di sistema (systemsettings5), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7faaf67f5780 (LWP 11959))]

Thread 5 (Thread 0x7faae401f700 (LWP 11960)):
#0  0x00007faaf2f598dd in poll () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007faaf1273b72 in ?? () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#2  0x00007faaf127564f in xcb_wait_for_event () from /usr/lib/x86_64-linux-gnu/libxcb.so.1
#3  0x00007faae6db2099 in ?? () from /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqxcb.so
#4  0x00007faaf35dab0e in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007faaf018d6aa in start_thread (arg=0x7faae401f700) at pthread_create.c:333
#6  0x00007faaf2f64eed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 4 (Thread 0x7faad4a56700 (LWP 11962)):
#0  0x00007faaf2f5549d in read () at ../sysdeps/unix/syscall-template.S:81
#1  0x00007faaec0d5f45 in ?? () from /usr/lib/nvidia-346/tls/libnvidia-tls.so.346.59
#2  0x00007faaefcb22f0 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007faaefc6e96c in g_main_context_check () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007faaefc6ee60 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007faaefc6efcc in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#6  0x00007faaf3871c6c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007faaf38163e2 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#8  0x00007faaf35d5b44 in QThread::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007faaf25a0f65 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#10 0x00007faaf35dab0e in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#11 0x00007faaf018d6aa in start_thread (arg=0x7faad4a56700) at pthread_create.c:333
#12 0x00007faaf2f64eed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 3 (Thread 0x7faacd0f0700 (LWP 11963)):
#0  0x00007faaefcb3789 in g_mutex_lock () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#1  0x00007faaefc6e409 in g_main_context_prepare () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007faaefc6ede8 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007faaefc6efcc in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007faaf3871c6c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007faaf38163e2 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#6  0x00007faaf35d5b44 in QThread::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#7  0x00007faaf25a0f65 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#8  0x00007faaf35dab0e in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007faaf018d6aa in start_thread (arg=0x7faacd0f0700) at pthread_create.c:333
#10 0x00007faaf2f64eed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 2 (Thread 0x7faac6a46700 (LWP 11964)):
#0  pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1  0x00007faaf35dbc6b in QWaitCondition::wait(QMutex*, unsigned long) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2  0x00007faaf204cfab in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#3  0x00007faaf204d3a0 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#4  0x00007faaf35dab0e in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#5  0x00007faaf018d6aa in start_thread (arg=0x7faac6a46700) at pthread_create.c:333
#6  0x00007faaf2f64eed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Thread 1 (Thread 0x7faaf67f5780 (LWP 11959)):
[KCrash Handler]
#6  0x00007faad52a76b7 in KDecoration2::Decoration::update(QRect const&) () from /usr/lib/x86_64-linux-gnu/libkdecorations2.so.5
#7  0x00007faad52a775b in KDecoration2::Decoration::update() () from /usr/lib/x86_64-linux-gnu/libkdecorations2.so.5
#8  0x00007faacd3ed370 in ?? () from /usr/lib/x86_64-linux-gnu/qt5/plugins/org.kde.kdecoration2/breezedecoration.so
#9  0x00007faacd40d7a8 in ?? () from /usr/lib/x86_64-linux-gnu/qt5/plugins/org.kde.kdecoration2/breezedecoration.so
#10 0x00007faaf35bb5ca in QPropertyAnimation::updateCurrentValue(QVariant const&) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#11 0x00007faaf35b6f48 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#12 0x00007faaf35b7d1b in QVariantAnimation::updateCurrentTime(int) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#13 0x00007faaf35b3baf in QAbstractAnimation::setCurrentTime(int) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#14 0x00007faaf35b3e96 in QUnifiedTimer::updateAnimationTimers(long long) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#15 0x00007faaf35b47dc in QAnimationDriver::advanceAnimation(long long) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#16 0x00007faaf20311ee in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#17 0x00007faaf204f68a in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#18 0x00007faaf2051a8b in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#19 0x00007faaf205230a in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#20 0x00007faaf40507b5 in QWindow::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#21 0x00007faaf2083dd3 in QQuickWindow::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#22 0x00007faaf4604b2c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#23 0x00007faaf460a000 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5
#24 0x00007faaf3818c2b in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#25 0x00007faaf4048e86 in QGuiApplicationPrivate::processExposeEvent(QWindowSystemInterfacePrivate::ExposeEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#26 0x00007faaf4049bbd in QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#27 0x00007faaf402e34f in QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5
#28 0x00007faae6ddc590 in ?? () from /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqxcb.so
#29 0x00007faaefc6ec3d in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#30 0x00007faaefc6ef20 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#31 0x00007faaefc6efcc in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#32 0x00007faaf3871c57 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#33 0x00007faaf38163e2 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#34 0x00007faaf381e02c in QCoreApplication::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#35 0x000000000040eebc in main ()

Reported using DrKonqi