The Status Icons documentation page describes the per-track match icons inaccurately.

It states the icons indicate "the quality of match between the information from the file and the information for the track as provided from the MusicBrainz database".

In reality the icon is driven by the file's pending-change state (File.similarity, how closely the data currently loaded in the file matches the data stored on disk) not the quality of the MusicBrainz match.

Two further inaccuracies:

• The six icons are captioned 50/60/70/80/90/100, but the actual levels are a "poor match" level below ~56%, four intermediate levels, and a level shown only for an exact 100% match.
• The relationship between the fully-green match icon and the saved (checkmark) icon is not explained: a perfect-green match icon still means there are unsaved changes, while the saved icon means the loaded data equals the data on disk.