Dear,
I had a problem with GIMP because of the gtk version with which it is compiled. This bug I mention the same and the solution was to rename /usr/lib/x86_64-linux-gnu/gtk-2.0/modules/libgail.so since the program crashed there.
In this https://bugzilla.gnome.org/show_bug.cgi?id=732859 link, you can see all the information about the problem. I think it's a bug in the version of gtk thus reported here.
Automatically closed -- issue fixed for 2 weeks with no activity.
This is fixed in the current Trisquel 7.0 beta. Please move to that version when it is released as stable.