How do I clone/copy a Map in JavaScript?

I know how to clone an array, but how do I clone/copy a Map?

var myArray = new Array(1, 2, 3);

var copy    = myArray.slice();

// now I can change myArray[0] = 5; & it wont affect copy array



// Can I just do the same for map?

var myMap = new ?? // in javascript is it called a map?

var myMap = {"1": 1, "2", 2};

var copy  = myMap.slice();