Application that crashed: nspluginviewer
Version of the application: 
KDE Version: 4.3.1 (KDE 4.3.1)
Qt Version: 4.5.3
Operating System: Linux 2.6.30-ARCH i686

What I was doing when the application crashed:
Well, I don't know if it is an useful backtrace, but, I will post it here

This happened when I was only browsing

 -- Backtrace:
Application: nspluginviewer (nspluginviewer), signal: Segmentation fault
[Current thread is 1 (Thread 0xb5ebe700 (LWP 27622))]

Thread 3 (Thread 0xb1193b70 (LWP 27747)):
#0  0xb80dc424 in __kernel_vsyscall ()
#1  0xb6610b95 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#2  0xb67c57cd in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libc.so.6
#3  0xb3dae78f in ?? () from /usr/lib/mozilla/plugins/libflashplayer.so
#4  0xb3edfb3f in ?? () from /usr/lib/mozilla/plugins/libflashplayer.so
#5  0xb3daec3d in ?? () from /usr/lib/mozilla/plugins/libflashplayer.so
#6  0xb660c65c in start_thread () from /lib/libpthread.so.0
#7  0xb67b81fe in clone () from /lib/libc.so.6

Thread 2 (Thread 0xb2576b70 (LWP 27748)):
#0  0xb80dc424 in __kernel_vsyscall ()
#1  0xb6610b95 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libpthread.so.0
#2  0xb67c57cd in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/libc.so.6
#3  0xb3dae78f in ?? () from /usr/lib/mozilla/plugins/libflashplayer.so
#4  0xb3edfb3f in ?? () from /usr/lib/mozilla/plugins/libflashplayer.so
#5  0xb3daec3d in ?? () from /usr/lib/mozilla/plugins/libflashplayer.so
#6  0xb660c65c in start_thread () from /lib/libpthread.so.0
#7  0xb67b81fe in clone () from /lib/libc.so.6

Thread 1 (Thread 0xb5ebe700 (LWP 27622)):
[KCrash Handler]
#6  0xb7e3fae6 in g_slice_alloc () from /usr/lib/libglib-2.0.so.0
#7  0xb7e40195 in g_slice_alloc0 () from /usr/lib/libglib-2.0.so.0
#8  0xb62532e7 in g_type_create_instance () from /usr/lib/libgobject-2.0.so.0
#9  0xb6238428 in g_object_constructor () from /usr/lib/libgobject-2.0.so.0
#10 0xb623960c in g_object_newv () from /usr/lib/libgobject-2.0.so.0
#11 0xb623a20a in g_object_new_valist () from /usr/lib/libgobject-2.0.so.0
#12 0xb623a38e in g_object_new () from /usr/lib/libgobject-2.0.so.0
#13 0xb3b2728c in gtk_plug_new_for_display () from /usr/lib/libgtk-x11-2.0.so.0
#14 0xb3b272d6 in gtk_plug_new () from /usr/lib/libgtk-x11-2.0.so.0
#15 0xb3da19cd in ?? () from /usr/lib/mozilla/plugins/libflashplayer.so
#16 0xb3d97581 in ?? () from /usr/lib/mozilla/plugins/libflashplayer.so
#17 0xb3d9bdb4 in ?? () from /usr/lib/mozilla/plugins/libflashplayer.so
#18 0x08fdb3c8 in ?? ()
#19 0xbfbf5a08 in ?? ()
#20 0xbfbf59a8 in ?? ()
#21 0xb7405d91 in QObjectPrivate::~QObjectPrivate() () from /usr/lib/libQtCore.so.4
#22 0x080502d8 in ?? ()
#23 0x0805e2c3 in ?? ()
#24 0x0805d615 in ?? ()
#25 0x08057cff in ?? ()
#26 0x0805e9ac in ?? ()
#27 0xb7ec2667 in ?? () from /usr/lib/libQtDBus.so.4
#28 0xb7ec370d in ?? () from /usr/lib/libQtDBus.so.4
#29 0xb7ec3fe4 in ?? () from /usr/lib/libQtDBus.so.4
#30 0xb7ec428a in ?? () from /usr/lib/libQtDBus.so.4
#31 0xb74013be in QObject::event(QEvent*) () from /usr/lib/libQtCore.so.4
#32 0xb6a44924 in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#33 0xb6a4c00c in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#34 0xb792f46a in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#35 0xb73f15ab in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#36 0xb73f21d2 in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from /usr/lib/libQtCore.so.4
#37 0xb73f239d in QCoreApplication::sendPostedEvents(QObject*, int) () from /usr/lib/libQtCore.so.4
#38 0xb741c0df in ?? () from /usr/lib/libQtCore.so.4
#39 0xb7e21d98 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#40 0xb7e253e0 in g_main_context_iterate () from /usr/lib/libglib-2.0.so.0
#41 0xb7e25513 in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#42 0xb741bd0c in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#43 0xb6ae2705 in ?? () from /usr/lib/libQtGui.so.4
#44 0xb73efb99 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#45 0xb73effea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#46 0xb73f245f in QCoreApplication::exec() () from /usr/lib/libQtCore.so.4
#47 0xb6a447a7 in QApplication::exec() () from /usr/lib/libQtGui.so.4
#48 0x0805c5f0 in ?? ()
#49 0xb6701a36 in __libc_start_main () from /lib/libc.so.6
#50 0x0804e511 in _start ()

Reported using DrKonqi