I also had this problem but I think it is gone now. Maybe because of some updates. I tried to reproduce the crash like it is described here - without success.
-- Gnome freezes with drag / drop to 2 different windows https://bugs.launchpad.net/bugs/223164 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
