Inject jQuery into a page

inject.javascript.js

%%javascript

function injectJavaScript(url) {
    var tag = document.createElement('script');
    tag.src = url;
    tag.type = 'text/javascript';
    tag.async = 'true';
    var hookTag = document.getElementsByTagName('script')[0];
    hookTag.parentNode.insertBefore(tag, hookTag);
}

;(function() {
    injectJavaScript('https://cdnjs.cloudflare.com/ajax/libs/require.js/2.3.6/require.min.js');
    injectJavaScript('https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js');
})();