Resolved -
The faulty service has been identified and rolled back to the previous working version. HipChat add-ons are now functioning via Atlassian Marketplace.
Apr 18, 12:14 UTC
Update -
We are continuing to investigate and will report updates here.
Apr 18, 10:50 UTC
Investigating -
We're aware of an issue with HipChat add-ons. We are investigating.
Apr 18, 10:00 UTC