Raku passes all the tests. He mentions he didn't find any language that upper-cases "baﬄe" correctly but Raku does.
Here's my REPL test
> my $n = "noe\xl"
> $n.substr(0, 3)
> my $b = "baﬄe"
> $b.substr(2, 1).uniname
LATIN SMALL LIGATURE FFL
> "noe\xl" eq "no\x[00EB]l"
We call it NFG for Normalized Form Grapheme.
Of further note, you can use ignorecase in regexes to match "baﬄe".
"baﬄe" ~~ /:ignorecase BAFfLE /;