title: How to append a value to a cookie in javascript
body: <p>It must have been 15 years since I set a cookie value with javascript ...</p>
  
  <pre><code>document.cookie = 'key=value';  //got that ...
  </code></pre>
  
  <p>How do I append another value with the same key? I want to create a list of values (page=1,34,48,59...) that I can then read and loop over. Or is there a better way?</p>