title: Format column header dates in FullCalendar
body: <p>I've been trying to change the format of the dates that appear in the day column headers on the Fullcalendar week/timegrid view:</p>
  
  <p><a href="https://i.stack.imgur.com/57rUN.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/57rUN.jpg" alt="enter image description here"></a></p>
  
  <p>I'm using V5 in conjuction with moment.js.</p>
  
  <p>Searching through the docs, I ended up here: <a href="https://fullcalendar.io/docs/v5/day-header-render-hooks" rel="noreferrer">https://fullcalendar.io/docs/v5/day-header-render-hooks</a></p>
  
  <p>This is the code I've tried when initialising the calendar:</p>
  
  <pre><code>dayHeaderFormat: function(date){
      return moment(date.weekday).format('ddd');
  }
  </code></pre>
  
  <p>This results in showing today (Thu) for every header, rather than the correct days.</p>
  
  <p>My next issue is that I'm not sure how to format the rest of the date accordingly - this targets the 'weekday' element of the date object, but I couldn't figure out how to format the whole date in one go (if that's possible). I'm looking to simply display 'Thu 14th', for example.</p>
  
  <p>Any help or advice appreciated!</p>