Basically the same as
MBS-4240 except I never get ISEs. I don't know exactly how to reproduce it, but since it just happened to me, it clearly is still reproducible somehow.
The edits in question are https://beta.musicbrainz.org/edit/19301414, https://beta.musicbrainz.org/edit/19301419 and https://beta.musicbrainz.org/edit/19301424 There were supposed to be three different releases, but they were all added as the last release I loaded the edit note tab for.
This is with Opera 12.01 in Linux but I've definitely seen it before in other versions of Opera in OSX.