I assume you mean seen but not visited, since as the other reply says, the browser tracks :visited for you.<p>I have a more aggressive greasemonkey script that hides lots of non-technical links on HN<p><pre><code>    var links = document.links;

    var boring = [ &quot;adage.com&quot;, &quot;arstechnica&quot;, &quot;bbc&quot;, &quot;discovermagazine&quot;, &quot;bloomberg&quot;, 
               &quot;bloombergview&quot;, &quot;buzzfeed&quot;, &quot;businessinsider&quot;, 
              &quot;californiasunday&quot;,&quot;cnn&quot;,&quot;csmonitor&quot;,&quot;dailymail&quot;,
              &quot;digg&quot;, &quot;economist&quot;,&quot;esquire&quot;, &quot;fastcompany&quot;,
              &quot;forbes&quot;, &quot;ft.com&quot;, &quot;fortune&quot;, &quot;fusion&quot;, &quot;geekwire&quot;,
              &quot;gizmodo&quot;, &quot;harvard.edu&quot;, &quot;huffingtonpost&quot;, &quot;inc.com&quot;,
              &quot;longreads&quot;, &quot;medium&quot;, &quot;mondaynote&quot;,
              &quot;nature&quot;, &quot;nautil.us&quot;, &quot;newscientist&quot;, &quot;newstatesman&quot;,
              &quot;newyorker&quot;, &quot;npr.org&quot;, &quot;nybooks&quot;, &quot;nymag&quot;, &quot;nytimes&quot;, &quot;pando&quot;,
              &quot;psychologytoday&quot;, &quot;qz.com&quot;, &quot;reddit&quot;, &quot;reuters&quot;, &quot;sciencedaily&quot;,
              &quot;scientificamerican&quot;, &quot;slate&quot;, &quot;techcrunch&quot;, &quot;telegraph&quot;,
              &quot;theatlantic&quot;, &quot;theguardian&quot;, &quot;thenation&quot;,&quot;theparisreview&quot;,
              &quot;theverge&quot;, &quot;theregister&quot;, &quot;time&quot;, &quot;usatoday&quot;, &quot;vancouversun&quot;,
              &quot;vice&quot;, &quot;vimeo&quot;,
              &quot;vogue&quot;, &quot;washingtonpost&quot;, &quot;wired&quot;, &quot;wsj&quot;, &quot;yahoo&quot;,
              &quot;youtube&quot;, &quot;zdnet&quot; ];
     matcher = new RegExp(&quot;\\b(&quot;+(boring.join(&quot;|&quot;).replace(&#x2F;\.&#x2F;g,&quot;\\.&quot;))+&quot;)\\b&quot;);
     for (i=0; i&lt;links.length; i++) {
       hostname = links[i].hostname.replace(&#x2F;^www\.&#x2F;,&quot;&quot;);
       if (hostname.match(matcher)) {
         links[i].style.setProperty(&quot;display&quot;, &quot;none&quot;);
  
         links[i].parentNode.insertBefore(document.createTextNode(&quot;[removed]&quot;), links[i]);

      }
    }
</code></pre>
Just to be clear, I read a lot of those sites - I&#x27;m just not interested in seeing them on HN, where I&#x27;m looking for technical news.<p>Anyway, you could adapt this by parsing the age field and making judgements based on how old the article is and your time of day (ie you&#x27;ll have seen a 6 hour old article at the end of the day, but at the start of the day, it first appeared overnight)