I cannot reproduce this. The backtrace only indicates qtwebkit as being unique here, but not where it all messed up (you need debugging symbols to actually get anything useful out of backtraces).

Could you do a dmesg right after the crash and see if there's anything new? Also, paste any output from command line, if any (I'm assuming it's simply a segfault).

I didn't have output in dmesg.
I add output.

Ok, thanks. Please backup and remove ~/.kde4 and ~/.local and then try again.

Please also always use a default standard shell when troubleshooting and reporting. If you are using Zsh, run kbibtex from a new Bash instance.

After removing ~/.kde4 and ~/.local and launch bash, the problem is still the same.
I also tried to create a new account, log in with a KDE session from GDM (I have intalled kde-base since I report the bug) and ever the same bug.

PS : I have tried on 3 different computers.

Thanks but actually I only wanted the output from running kbibtex after you had backed up and removed ~/.kde4 and ~/.local. Nothing else is necessary:

mv .kde4 .kde4.bak # or gnome2/gnome3, basically any WM/DE config dir
mv .local .local.bak
reboot # to clear out all temporary data
# login to a fresh kde/gnome/whatever
# open console/terminal
bash
kbibtex # now see what is the output

I have almost the same relevant packages (and versions) as you, except qt5. However, your kbibtex output contains a lot of unwanted information.

I will try to get someone else to reproduce. I suspect kbibtex is misbehaving due to something that I do not have installed, or due to conflicts between GTK/Qt/KDE styles that it cannot handle.

Another thing you can do: grab kbibtex from ABS, makepkg -o, navigate into the source, follow the PKGBUILD and do a make. Then run the binary from there (do NOT install). Do this while you have kbibtex from the repos installed (so that the deps are installed for you to pass the configuration and build).

Whatever it is, kbibtex should run from whatever DE/WM you have with whatever default style there is. If it does not, it's a bug. So don't go through the trouble of logging into KDE (it's just a dep of kbibtex) if that's not what you use.

I found the problem. Kbibtex try to launch okular and segfault because I haven't install it. After installing okular, it is all fine.
So please add okular as dependancy.

Great that it solved your problem, but it's unfortunate that kbibtex requires an actual KDE app as a dependency. It is now reproducible, with okular gone.

Thanks for your patience in troubleshooting this, I will be adding the dep as well as reporting this nasty effect upstream.