Comment 2 for bug 1738870

     This is becoming even more of a persistent issue now. According to Carlos Soriano on the Gnome Desktop Development [Mailing] List, it's been proposed migrating the entire bug tracking system over to Gitlab: https://mail.gnome.org/archives/desktop-devel-list/2018-March/msg00023.html

     Even if Gnome decides to go against the mass migration to Gitlab, many project bug trackers within the Gnome community are hosted within Gitlab anyways, and those links are not supported for some reason in Launchpad as valid bug tracker URLs/IDs.

     Canonical, please update Launchpad.