JSFiddle - React, Tailwind, and code Playground

HTML

<a href="javascript:log(++i);">OOO</a><br/>
<a href="http://codepad.viper-7.com/dRwtne.php53">Referrer check</a>

Test: delayed click: <input type="text" id="secs" /><br />
<textarea id="log">Quick demo for Firefox and Chrome</textarea>

CSS

html,body{height:100%;}
#secs {
    width: 4em;
    padding: 5px;
    text-align: center;
}
#log {
    white-space: pre;
    font-family: monospace;
    font-size: 15px;
    height: 80%;
    width: 95%;
    border: 1px solid #555;
    padding: 5px;
}

JavaScript

var i = 0, j=0, secs = 4;
window.onload = function(){
    var s=document.getElementById('secs');
    s.onkeyup = function() {
        var draft = parseFloat(this.value);
        if (!isNaN(draft)) {
            secs = draft;
            this.style.backgroundColor = '';
        } else {
            this.style.backgroundColor = 'pink';
        }
    };
    s.value = secs;
                     
    var isWebkit = document.createElement("a");
    isWebkit.style.cssText = "-webkit-border-radius:1px;";
    isWebkit = isWebkit.style.cssText.indexOf("radius") !== -1;
    if (isWebkit) chromeMethod();
    else firefoxMethod();
    function chromeMethod() {
       // Create a data-URI, redirection by <meta http-equiv=refresh content="0;url=..">
        function doNotTrack(url) {
           // As short as possible. " can potentially break the <meta content> attribute,
           // # breaks the data-URI. So, escape both characters.
           var url = url.replace(/"/g,'%22').replace(/#/g,'%23');
           // In case the server does not respond, or if one wants to bookmark the page,
           //  also include an anchor. Strictly, only <meta ... > is needed.
           url = '<title>Redirect</title>'
               + '<a href="' +url+ '" style="color:blue">' +url+ '</a>'
               + '<meta http-equiv=refresh content="0;url=' +url+ '">';
           return 'data:text/html,' + url;
        }
        function hideRefer(e) {
           var a = e.target;
           if (a && a.tagName !== 'A') a = a.parentNode;
           if (a && a.tagName === 'A') {
              if (e.type == 'contextmenu' || e.button < 2) {
                 var realHref = a.href; // Remember original URI
                 // Replaces href attribute with data-URI
                 a.href = doNotTrack(a.href);
                 // Restore the URI, as soon as possible
                 setTimeout(function() {a.href = realHref;}, 4);
              }
           }
        }
       ...