else don't list it first.
In inverted bracketed character classes, Perl ignores the Unicode rules
-that normally say that certain characters match a sequence of multiple
-characters under caseless C</i> matching. Following those rules
-can lead to highly confusing situations:
+that normally say that certain characters should match a sequence of
+multiple characters under caseless C</i> matching. Following those
+rules could lead to highly confusing situations:
"ss" =~ /^[^\xDF]+$/ui; # Matches!