Some basic utils often missed within Javascript
usage examples that will work within the script or a webbrowser console of your choice and preference:
console.log('Just testing something really cool I guess.'.startsWith(''));
console.log("Contains Test: " + 'Does this contain this?'.contains('Does'));
console.log("Contains Test: " + '2'.contains(2));
var s = '';
console.log("EmptyString Test: " + s.emptyString());
var someWeirdString = "Testing another string";
console.log(someWeirdString.startWith("Test"));
// returns true;
console.log(someWeirdString.reverse();
// returns "gnirts rehtona gnitseT"