The examples they give all look like valid uses of different Non-breaking spaces, with width hints for their use/location, this might be a little overzealous if

The examples they give all look like valid uses of different Non-breaking spaces, with width hints for their use/location, this might be a little overzealous if written by a human but perhaps not for a machine. https://en.wikipedia.org/wiki/Non-breaking_space https://en.wikipedia.org/wiki/Non-breaking_space Different display apps may "display them identically" but others and typesetters/printing apps might not.