You are right. I can confirm this. I don't think it's a real bug, more a feature- wish. Perhaps you should report this directly in http://bugzilla.gnome.org/ ?
** Changed in: epiphany-browser (Ubuntu) Status: Unconfirmed => Confirmed -- Epiphany does not warn when closing a window with multiple tabs https://launchpad.net/bugs/51658 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs