MusicBrainz release performer metadata saved into arranger frame

Since the last Kid3 release (I think) I've been noticing that the Performer frame offered by MusicBrainz is been saved into the Arranger frame, which is highlighted in red when there's another Arranger frame present for the track.

So, there's id3 tags with two Arranger frames, with the second one colored in red, containing Performer metadata.

I'm using Kid3 3.5.1 compiled on Debian Stretch.