"Invalid regular expression" when /s flag is used on long RegExps

[dse]

When sufficiently long regular expressions with the /s (dotAll) flag are used I always get an Invalid regular expression error. Reasonably minimal test case:

/*jshint esversion: 9 */
let rx;
rx = /a./s;
rx = /abcd.efgh/s;
rx = /abcd.efghiijklmnopq/s;
rx = /abcd.efghiijklmnopqr/s;
/* 7 */ rx = /abcd.efghiijklmnopqrs/s;
/* 8 */ rx = /abcd.efghiijklmnopqrst/s;
/* 9 */ rx = /abcd.efghiijklmnopqrstuv/s;
/* 10 */ rx = /abcd.efghiijklmnopqrstuvwxyz/s;

jshint output:

$ jshint ~/foo.js
/home/dembry/foo.js: line 7, col 14, Invalid regular expression.
/home/dembry/foo.js: line 8, col 14, Invalid regular expression.
/home/dembry/foo.js: line 9, col 14, Invalid regular expression.
/home/dembry/foo.js: line 10, col 15, Invalid regular expression.

4 errors

jshint version:

$ jshint --version
jshint v2.13.6

node version

$ node --version
v18.19.0

I can't find anything in the documentation about /s even being a problem at all.

This issue goes at least as far back as jshint 2.10.

This also occurs on the web demo.