Arch Linux

It crashes because it tries to load Qt4 library (libQtGui).
Does it crash right at the startup, or when already browsing?
Crash at the startup may be caused by loading KWalletPasswords plugin (which is only for Qt4).
Crash during browsing may be caused by some Qt4 NPAPI plugin.

It does not crash at startup and it is able to render quite simple websites like kernel.org without crashing.
However if you point it to some more complex (maybe more javascript intensive) site it will crash.
By looking at the crashlog it seems that the problems are in the Qt5WebKit library.

If I have time i'll reinstall the qt5 version and try to "gdb" it.

I'm not sure but I suspect that the problem arose after the latest qt5 update.
qupzilla is a few days older than qt5.

If the backtrace you attached is correct, then it is crashing upon loading dynamic library that is linked against Qt4 (thus loading libQtGui).
The issue is NOT in QtWebKit in this case.

If it crashes on browsing, then it must be loading (probably) some NPAPI plugin that is using Qt4 (so you should be able to trigger this crash by loading qupzilla:config).

I simply uninstalled qupzilla-qt4 and reinstalled qupzilla (qt5) and it appears to be stable now.
No more crashes. O_o ...

It looks like Qt 5.3 brings more stability to qupzilla. Can I close this?

It looks like Qt 5.3 brings more stability to qupzilla. Should I close this?

I just updated qt5 to version 5.3.0-3 and now qupzilla crashes when looking to a video from youtube and click to jump forward in the video.
The message on the terminal:

libpng warning: iCCP: Not recognizing known sRGB profile that has been edited (image/qpnghandler.cpp:499, void qt_png_warning(png_structp, png_const_charp))
QupZilla: 0 extensions loaded
QupZilla: Crashed :( Saving backtrace in /home/fred/.config/qupzilla/crashlog ...
Backtrace successfuly saved in /home/fred/.config/qupzilla/crashlog/Crash-2014-05-30T09:57:05.txt

Backtrace added

The YouTube jumping issue is now reported upstream https://github.com/QupZilla/qupzilla/issues/1505 let's see.

while the qt4 version works stable (gmail complains because it is no more supported), qupzilla qt5, after being stable for a quite long while, has restarted to crash :(

Obviusly it depends on some other system library upgrade, but it is starting to be a bit frustrating.

The following backtrace has been obtained while trying to open www.mozilla.org, it crashes also on gmail.com. Works for simple sites like
kernel.org.

Time: Fri Dec 5 09:26:23 2014
Qt version: 5.3.2 (compiled with 5.3.2)
QupZilla version: 1.8.4
WebKit version: 538.1

============== BACKTRACE ==============
#0: /usr/bin/qupzilla() [0x4033ab]
#1: /usr/lib/libc.so.6(+0x33b20) [0x7ff3bd7feb20]
#2: /usr/lib/libQtGui.so.4(+0x1b452c) [0x7ff2a9d6152c]
#3: /lib64/ld-linux-x86-64.so.2(+0xf24a) [0x7ff3c1c8b24a]
#4: /lib64/ld-linux-x86-64.so.2(+0xf35b) [0x7ff3c1c8b35b]
#5: /lib64/ld-linux-x86-64.so.2(+0x137e7) [0x7ff3c1c8f7e7]
#6: /lib64/ld-linux-x86-64.so.2(+0xf0f4) [0x7ff3c1c8b0f4]
#7: /lib64/ld-linux-x86-64.so.2(+0x12e93) [0x7ff3c1c8ee93]
#8: /usr/lib/libdl.so.2(+0x1039) [0x7ff3b6879039]
#9: /lib64/ld-linux-x86-64.so.2(+0xf0f4) [0x7ff3c1c8b0f4]
#10: /usr/lib/libdl.so.2(+0x1609) [0x7ff3b6879609]
#11: /usr/lib/libdl.so.2(dlopen+0x31) [0x7ff3b68790d1]
#12: /usr/lib/libQt5Core.so.5(+0x284f0b) [0x7ff3be317f0b]
#13: /usr/lib/libQt5Core.so.5(_ZN8QLibrary4loadEv+0x98) [0x7ff3be312c88]
#14: /usr/lib/libQt5WebKit.so.5(+0xa2d104) [0x7ff3bf9dd104]
#15: /usr/lib/libQt5WebKit.so.5(+0x942806) [0x7ff3bf8f2806]
#16: /usr/lib/libQt5WebKit.so.5(+0x940b4e) [0x7ff3bf8f0b4e]
#17: /usr/lib/libQt5WebKit.so.5(+0x9414cb) [0x7ff3bf8f14cb]
#18: /usr/lib/libQt5WebKit.so.5(+0x48fb3c) [0x7ff3bf43fb3c]
#19: /usr/lib/libQt5WebKit.so.5(+0x87e84e) [0x7ff3bf82e84e]
#20: /usr/lib/libQt5WebKit.so.5(+0x86209f) [0x7ff3bf81209f]
#21: /usr/lib/libQt5WebKit.so.5(+0x87ec69) [0x7ff3bf82ec69]
#22: /usr/lib/libQt5WebKit.so.5(+0xf2dd3d) [0x7ff3bfeddd3d]
#23: /usr/lib/libQt5WebKit.so.5(+0x16d84f4) [0x7ff3c06884f4]
#24: /usr/lib/libQt5WebKit.so.5(+0x16d8f33) [0x7ff3c0688f33]
#25: /usr/lib/libQt5WebKit.so.5(+0x19b68b6) [0x7ff3c09668b6]
#26: /usr/lib/libQt5WebKit.so.5(+0x19b030a) [0x7ff3c096030a]
#27: /usr/lib/libQt5WebKit.so.5(+0x19baa95) [0x7ff3c096aa95]

Sorry , I mistakenly reposted the above one and can't delete

Can you please try with Qt 5.4?

I opened this [1], the patch should finally solve all this.
@Jamp Please try this already patched qt5-webkit build [2] and let me know.

[1] https://bugs.archlinux.org/task/43016
[2] http://pkgbuild.com/~speps/pkgs/qt5-webkit-5.3.2-2-x86_64.pkg.tar.xz

With the just released 5.4 version it works again
@speps.. sorry I hadn't tried your solution yet.
It's better to go with your patched webkit or Qt 5.4
has eventually fixed these problems?

Thanks,

The linked patch is already in Qt 5.4. So using either patched Qt 5.3 or offical 5.4 release should be fine.