PSA for Lemmy instance admins: in backend v0.18.3 there is a bug that causes your instance to stop federating properly and to stop sending out outgoing messages - Lemmy.ca direct link

This new version introduced a system so that your instance stops sending out content to other instances that are supposedly dead / offline. Unfortunately for some reason there’s false positives. When I checked comparing the results from a curl request vs the information in our Lemmy database I found...