rails/activestorage/CHANGELOG.md

• Saving attachment(s) to a record returns the blob/blobs object

  Previously, saving attachments did not return the blob/blobs that were attached. Now, saving attachments to a record with #attach method returns the blob or array of blobs that were attached to the record. If it fails to save the attachment(s), then it returns false.

  Ghouse Mohamed

• Don't stream responses in redirect mode

  Previously, both redirect mode and proxy mode streamed their responses which caused a new thread to be created, and could end up leaking connections in the connection pool. But since redirect mode doesn't actually send any data, it doesn't need to be streamed.

  Luke Lau

Please check 7-0-stable for previous changes.