IIRC, upstream GNOME/mutter has done some fixes for dual-link displays recently but upstream mostly only care about Wayland. So you might have more luck using 'Ubuntu on Wayland'.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1886729 Title: Dell displayport YJ3Y6 adapter doesn't drive 4K screen properly To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1886729/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs