I can reproduce (although not 100% of the times) on desktop too. Here is how the backtrace looks like when ran in gdb:
#0 QCoreApplication::postEvent (receiver=0x3b78820, event=0x7fff40041990, priority=0) at kernel/qcoreapplication.cpp:1284 #1 0x00007ffff649945e in QQuickPixmapReader::processJob (this=0x3984d80, runningJob=0x3b78820, url=..., requestSize=...) at util/qquickpixmapcache.cpp:563 #2 0x00007ffff6499f84 in QQuickPixmapReader::processJobs (this=0x3984d80) at util/qquickpixmapcache.cpp:526 #3 0x00007ffff649a2bd in QQuickPixmapReaderThreadObject::event (this=<optimized out>, e=<optimized out>) at util/qquickpixmapcache.cpp:480 #4 0x00007ffff593b16c in QApplicationPrivate::notify_helper (this=0x672610, receiver=0x7fff400013a0, e=0x3b6dd70) at kernel/qapplication.cpp:3504 #5 0x00007ffff594041e in QApplication::notify (this=0x7fffffffdc70, receiver=0x7fff400013a0, e=0x3b6dd70) at kernel/qapplication.cpp:3287 #6 0x00007ffff797981b in QCoreApplication::notifyInternal (this=0x7fffffffdc70, receiver=0x7fff400013a0, event=event@entry=0x3b6dd70) at kernel/qcoreapplication.cpp:935 #7 0x00007ffff797b7e3 in sendEvent (event=0x3b6dd70, receiver=<optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:237 #8 QCoreApplicationPrivate::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0, data=0x3980450) at kernel/qcoreapplication.cpp:1539 #9 0x00007ffff797bde8 in QCoreApplication::sendPostedEvents (receiver=receiver@entry=0x0, event_type=event_type@entry=0) at kernel/qcoreapplication.cpp:1397 #10 0x00007ffff79d0a63 in postEventSourceDispatch (s=0x7fff400012d0) at kernel/qeventdispatcher_glib.cpp:279 #11 0x00007ffff3c3ec5d in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0 #12 0x00007ffff3c3ef48 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0 #13 0x00007ffff3c3effc in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0 #14 0x00007ffff79d0e57 in QEventDispatcherGlib::processEvents (this=0x7fff400008c0, flags=...) at kernel/qeventdispatcher_glib.cpp:426 #15 0x00007ffff7977042 in QEventLoop::exec (this=this@entry=0x7fff55f3bdd0, flags=..., flags@entry=...) at kernel/qeventloop.cpp:212 #16 0x00007ffff773b4a4 in QThread::exec (this=this@entry=0x3984d80) at thread/qthread.cpp:511 #17 0x00007ffff649a346 in QQuickPixmapReader::run (this=0x3984d80) at util/qquickpixmapcache.cpp:688 #18 0x00007ffff77402ee in QThreadPrivate::start (arg=0x3984d80) at thread/qthread_unix.cpp:345 #19 0x00007ffff4ab90a5 in start_thread (arg=0x7fff55f3c700) at pthread_create.c:309 #20 0x00007ffff4dc984d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111 It seems the issue is with the custom FaviconImageProvider class when a request for a favicon is issued and almost instantly cancelled. ** Changed in: webbrowser-app Importance: Undecided => Critical ** Changed in: webbrowser-app Status: New => Confirmed ** Changed in: webbrowser-app Assignee: (unassigned) => Olivier Tilloy (osomon) ** Also affects: webbrowser-app (Ubuntu) Importance: Undecided Status: New ** Changed in: webbrowser-app (Ubuntu) Status: New => Confirmed ** Also affects: webbrowser-app (Ubuntu RTM) Importance: Undecided Status: New ** Changed in: webbrowser-app (Ubuntu RTM) Status: New => Confirmed ** Changed in: webbrowser-app (Ubuntu) Assignee: (unassigned) => Olivier Tilloy (osomon) ** Changed in: webbrowser-app (Ubuntu RTM) Assignee: (unassigned) => Olivier Tilloy (osomon) -- You received this bug notification because you are a member of Ubuntu WebApps bug tracking, which is subscribed to webbrowser-app. https://bugs.launchpad.net/bugs/1395748 Title: Crash going back twice while loading a page Status in Web Browser App: Confirmed Status in “webbrowser-app” package in Ubuntu: Confirmed Status in “webbrowser-app” package in Ubuntu RTM: Confirmed Bug description: Test case. - Go to start.ubuntu.com - After it loads, go to slashdot.org - After it loads, go to linux.com - While it is loading, tap to back button twice to go back to start.ubuntu.com Expected result. - Browser displays start.ubuntu.com Actual result. - Crash. current build number: 118 device name: krillin channel: ubuntu-touch/ubuntu-rtm/14.09.es-proposed To manage notifications about this bug go to: https://bugs.launchpad.net/webbrowser-app/+bug/1395748/+subscriptions -- Mailing list: https://launchpad.net/~ubuntu-webapps-bugs Post to : ubuntu-webapps-bugs@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-webapps-bugs More help : https://help.launchpad.net/ListHelp