var mappedRequestURI = "";
var mappedRequestURIString = "";
var req = new XMLHttpRequest();
req.open('HEAD', document.location, false);
req.send(null);
if (req.getResponseHeader("PX-Mapped-Request-URI") || req.getResponseHeader("px-mapped-request-uri")) {
	mappedRequestURIString = req.getResponseHeader("PX-Mapped-Request-URI") || req.getResponseHeader("px-mapped-request-uri");
	let stringToTest = mappedRequestURIString.match(/^\/(?:[a-z0-9-_]+\/)?/)[0];
	if (stringToTest != null || stringToTest != undefined) {
		mappedRequestURI = stringToTest;
	}
} else {
	mappedRequestURI = "/";
}

document.getElementsByTagName("base")[0].setAttribute("href", mappedRequestURI);