Under the hoodTier: how much it should matter to you
1Useful: my rating, 1 to 5
1Signal: worth watching, 1 to 5
InternalsArea: what it touches
ImprovementsKind: in v2.1.242,
ImprovementsSection of the release
What
Two identifier checks that accepted names of any length now cap them at 64 characters, the line-start matcher recognises the U+001C to U+001E separator characters, and the routine that strips invisible characters was replaced with a broader Unicode class match.
Evidence
/^[A-Z][a-zA-Z]{0,63}$/
Strings lifted out of the shipped bundle, so the claim above can be checked against them.