Thanks a lot, Jonathan, for your very helpful comment. Indeed, I installed (by mistake) a package that depended on "ubuntu-mobile- default-settings". Removing this package solved the problem :-)
** Changed in: ubuntu Status: New => Invalid -- Titlebars of all windows disappeared https://bugs.launchpad.net/bugs/596449 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