I am looking at the following release: https://musicbrainz.org/release/d1bc3717-ac5e-449e-9ce0-ddfc5da4627e

The first medium clearly has each recording highlighted.

This is also visible if looking at the list of recordings entered against the medium artist(s).

However, there do not appear to be any edits open against these recordings.

Indeed, there are no edits open for Nucleus, and the only edits open for Ian Carr relate to entirely different recordings.

There are no performance relationship entered against these recordings, either.

I opened the release in a different browser, in which I am not logged in, and the highlights are still visible.