I tried to add a new release for THE PREDATORS and got a weird error message when I clicked on the "Submit edits" button. The little processing gif appeared for a few moments before the error message appeared (screenshot attached).
I hit "Submit edits" again twice but got the same error.
When I check my open edits, the actual release seemed to be created, but the Label and Catalogue number edit seemed to be duplicated (probably because I hit the "Submit edits" button again. Duplicates screenshots attached).
I was able to cancel the duplicate edits without any problems.
The release affected is here: https://musicbrainz.org/release/144a2a94-2567-45d0-a1d7-b4ebd8a3ad67
I added a few relationships to URLs which didn't actually become edits and my annotation edit didn't go through either.
I'm going to try and add those edits separately now, will comment with results.