Unable to follow remote accounts on Mitra/Akkoma

[julianlam]

Follow problems with Akkoma and Mitra accounts might be related; same follow id or accept id issue?

[oplik0]

There were two issues here:

1. we didn't send an ID along with the Follow activity (see Send a unique id for all ActivityPub server-to-server events #12483)
2. we fully rejected activities with objects when their id didn't match the activity's origin

The latter was done for security reason, but meant that a lot of activities either couldn't work or would break with compliant implementations. Now instead such mismatched objects are stripped down to just their ids and then retrieved from origin (once FEP-8b32 is finalized and implemented it should allow to skip this additional download for signed objects)