Dimitri, I've performed your tasks and can confirm with that PPA applied that it works properly. I've emailed you the packet captures privately to your @ubuntu.com address.
I also do note the following in my journal log: Mar 26 12:18:43 test-XPS-13-9350 systemd-resolved[507]: DVE-2018-0001 DOWNGRADING to feature level UDP for transaction 10122. Mar 26 12:18:43 test-XPS-13-9350 systemd-resolved[507]: DVE-2018-0001 DOWNGRADING to feature level UDP for transaction 29698. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1727237 Title: systemd-resolved is not finding a domain To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1727237/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs