Don’t know any such built-in feature. Writing a macro for that would be quite easy, however.

I can think of another, rather weird method: build an MM font with the old and the new one as masters. Those that are not compatible will not turn green so you have a first indication of modified glyphs. Then, generate an instance at an extreme extrapolation, say, 25000. Then you should be able to spot the changed glyphs – they will look strange and messy. I remember having done that once.

Tim,

an excellent solution — I never thought about this :)

A.