According to the String.prototype.replace() page on MDN, I should be able to easily replace multiple patterns just by using
str.replace(\'what to replace\',
From Mozilla Developer Network - JavaScript - String - replace
Non-standard
The use of the flags parameter in the String.replace method is non-standard. For cross-browser compatibility, use a RegExp object with corresponding flags.
Working in Chrome and Firefox
To get your code to work in Chrome and Firefox, you'll have to create a RegExp object (since your strings aren't hardcoded) with the appropriate flags. See Mozilla Developer Network - RegExp