I'm not sure how many of these are the same problem in different forms, so whatever, one ticket.

To reproduce:

• Load https://beta.musicbrainz.org/release/add?release-group=cbbae316-bb2e-4847-83a7-d706831bb1f5
• Click on the similar releases tab, select the existing release and continue to the tracklist
• Click the recordings tab, edit the first recording and select add a new recording
• Click the edit note tab

Problem 1: Track 1 is still linked to the existing recording.

• Enter an edit note and try to submit

Problem 2: Add medium edit fails with "unknown Recording id: at lib/MusicBrainz/Server/Controller/WS/js/Edit.pm line 417, <$fh> line 1." after the release is created, leaving it with no tracklist.

• Load https://beta.musicbrainz.org/release/add?release-group=cbbae316-bb2e-4847-83a7-d706831bb1f5 again
• Click on the similar releases tab, select the existing release and continue to the tracklist
• Change track 1 to "Foo"
• Click the recordings tab, edit the first recording and select add a new recording
• Click the edit note tab

Problem 3: Edit previews fail to load

Tested in both Opera and Chromium in OSX.