Snort generates a false positive on this line in piwik.js:
escapable = new RegExp('[\\\\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]', 'g'),
The Snort rule doesn't check for a closing ] (which was the Mozilla bug that this rule was supposed to detect).
(In ) fixes #2203
(In ) refs #2203 - add unit test for regressions