Same here. Yesterday I just returned from 2 weeks holiday and nothing was released in the meantime. This is serious!
[EDIT] I confirm that one of our apps - Issue Templates for Jira Cloud can’t be installed since Feb 14 09:48:12 UTC.
It is built using ACE - “atlassian-connect-express”: “^4.0.1”
What is very strange is that, the other app we have, which uses the exact format for installed hook works fine…
I have found a difference between two apps. In Issue Templates in config.json:
I had an additional slash at the end of the url.
This worked fine before, but I guess that Atlassian did some cleaning of their code lately and it broke that.
I have just released the fix and can confirm it fixes the issue.