Event listener to check if window/tab is active or inactive

active-tab.js

$(window).on("blur focus", function (e) {
    var prevType = $(this).data("prevType");
    if (prevType != e.type) {   //  reduce double fire issues
	switch (e.type) {
	    case "blur":
		// do work
		console.log('blurred');
		break;
	    case "focus":
		// do work
		console.log('activated');
		break;
	}
    }
    $(this).data("prevType", e.type);
});