unicode ligature

Ironically, the deprecated [fi] “LATIN SMALL LIGATURE FI” is less of a ligature in some fonts than ASCII f+i. It isn't required to be stylistically merged fi (connected or dotless etc), just be f+i in a single glyph, for legacy support.

that's from the top unicode expert https://twitter.com/FakeUnicode . Over the past 4 years i've learned a lot esoteric tech details about unicode from him.