Comment 2 for bug 1332968

StacktraceTop:
 strrchr () at ../sysdeps/x86_64/strrchr.S:32
 _gtk_menu_tracker_item_new (observable=0x1d85d80, model=model@entry=0x1db1b80, item_index=item_index@entry=5, action_namespace=0x1e03bb0 "indicator.thunderbird", is_separator=is_separator@entry=0) at /build/buildd/gtk+3.0-3.12.2/./gtk/gtkmenutrackeritem.c:524
 gtk_menu_tracker_add_items (tracker=tracker@entry=0x1d89390, change_point=change_point@entry=0x2431d88, offset=offset@entry=8, model=model@entry=0x1db1b80, position=position@entry=5, n_items=0, n_items@entry=1, section=0x1d91060) at /build/buildd/gtk+3.0-3.12.2/./gtk/gtkmenutracker.c:342
 gtk_menu_tracker_model_changed (model=0x1db1b80, position=5, removed=0, added=1, user_data=0x1d89390) at /build/buildd/gtk+3.0-3.12.2/./gtk/gtkmenutracker.c:445
 ffi_call_unix64 () at ../src/x86/unix64.S:76