Further to comment #8, the upstream bug was closed "VERIFIED FIXED" on 2019-02-21 with an additional report of being fixed on Ubuntu.
** Changed in: firefox (Ubuntu) Status: Incomplete => Fix Released -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1810902 Title: firefox picks unpredictable window for opening new content when using i3 as a window manager To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1810902/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs