Thanks for the information. Feel free to change things like this. (https://osm.org/changeset/168093723)

In this case I only want to remove the tailing equals sign in the tag 'source:ref='. And 'source_ref' is a commonly used tag for a source reference. 'source:ref' means commonly a the source of a ref tag. See the discussion in https://osm.org/changeset/34935063