What existing code could changing $ to use \R instead of \n potentially break? Could this raise security issues by widening input validation patterns?

A bit difficult to say, as even \n is not just a LF but a "logical newline", as described in perlrebackslash:

\n matches a logical newline. Perl converts between \n and your OS's native newline character when reading from or writing to text files.
And because it is so hard to tell I wouldn't want to change the meaning of $ without explicit request to do so for a single regex or within a lexical scope, i.e. by a flag or pragma.

Greetings,
-jo

$gryYup$d0ylprbpriprrYpkJl2xyl~rzg??P~5lp2hyl0p$

In reply to Re^6: Making $ Unicode-aware by jo37
in thread Making $ Unicode-aware by jo37

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