To add more color to this, the precise details of what "Unicode support" means are documented here: https://github.com/rust-lang/regex/blob/master/UNICODE.md
In effect, all of UTS#18 Level 1 is covered with a couple caveats. This is already a far cry better than most regex engines, like PCRE2, which has limited support for properties and no way to do subtraction or intersection of character classes. Other regex engines, like Javascript, are catching up. While UTS#18 Level 1 make ripgrep's Unicode support better than most, it does not make it the best. The third party Python `regex` library, for example, has very good support, although it is not especially fast[1].
Short of building UTS#18 2.1[2] support into the regex engine (unlikely to ever happen), it's likely ripgrep could offer some sort of escape hatch. Perhaps, for example, an option to normalize all text searched to whatever form you want (nfc, nfd, nfkc or nfkd). The onus would still be on you to write the corresponding regex pattern though. You can technically do this today with ripgrep's `--pre` flag, but having something built-in might be nice. Indeed, if you read UTS#18 2.1, you'll note that it is self-aware about how difficult matching canonical equivalents is, and essentially suggests this exact work-around instead. The problem is that it would need to be opt-in and the user would need to be aware of the problem in the first place. That's... a stretch, but probably better than nothing.
[1]: https://github.com/BurntSushi/rebar?tab=readme-ov-file#summa...
[2]: https://unicode.org/reports/tr18/#Canonical_Equivalents
