// Open timer popup
var result = window.open(
	location.protocol + "//" + location.host + "/popup" + location.search,
	"PopupTimer" + Date.now(),
	"width=250,height=100,menubar=no,toolbar=no,location=no,status=no,resizable=no,scrollbars=no"
);

// Show warning if it didn't work
if (!result) {

	document.getElementById("popup-warning").style.display = "block";
	document.getElementById("refresh").onclick = function() {
		location.reload();
	}

} else {
	window.onfocus = function() {
		history.back();
	}
}