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.
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: resolved[ 507]: DVE-2018-0001 DOWNGRADING to feature level UDP for transaction 10122. resolved[ 507]: DVE-2018-0001 DOWNGRADING to feature level UDP for transaction 29698.
Mar 26 12:18:43 test-XPS-13-9350 systemd-
Mar 26 12:18:43 test-XPS-13-9350 systemd-