Disable Polymer YouTube - Userscript

// ==UserScript==
// @name        Disable Polymer YouTube
// @match       *://*.youtube.com/*
// @run-at      document-start
// @grant       none
// ==/UserScript==

//Not the fastest, but please improve as you see fit.

try {
    var url = document.location.toString();
    var updateUrl = updateQueryStringParameter(url, 'disable_polymer', 'true');
    console.log(updateUrl);
    console.log(url != updateUrl);
    if (url != updateUrl) {
        document.location = updateUrl;
    }
} catch (e) {}

function updateQueryStringParameter(uri, key, value) {
    var re = new RegExp("([?&])" + key + "=.*?(&|$)", "i");
    var separator = uri.indexOf('?') !== -1 ? "&" : "?";
    if (uri.match(re)) {
        return uri.replace(re, '$1' + key + "=" + value + '$2');
    } else {
        return uri + separator + key + "=" + value;
    }
}