Tangential - I'm aware of various types of, let's say, "swappability" that Unicode defines (broader than the Unicode concept of "equivalence"):

- Canonical (NF)

- Compatible (NFK)

- Composed vs decomposed

- Confusable (confusables.txt)

Does Unicode not define something like "fuzzy" equivalence? Like "confusable" but more broad, for search bar logic? The most obvious differences would be case and diacritic insensitivity (e, é). Case is easy since any string/regex API supports case insensitivity, but diacritic insensitivity is not nearly as common, and there are other categories of fuzzy equivalence too (e.g. ø, o).

I guess it makes sense for Unicode to not be interested in defining something like this, since it relates neither to true semantics nor security, but it's an incredibly common pattern, and if they offered some standard, I imagine more APIs would implement it.