I can’t see it in the handbook. I thought it would match a regex, but it doesn’t seem to do anything.
It should be regex. But maybe a different flavour than you are expecting? I tried ([a-c]) and this worked (showing three letters).
OK, this is strange - it works on one Glyphs file but not another…
With the same glyph names in each file?
Note that the regex matches against the entire glyph name. So, when you use something like Georg’s example of [a-c], it’s the equivalent of the ^[a-c]$ regex.
Ah, that would make sense. I thought “.” should match all glyphs, didn’t realise it was start-to-end. Please add to the manual!