title: fullCalendar (v5) callback/handler anytime view is rendered?
body: <p>What is the way to catch anytime a view is rendered?</p>
  <p>Not only when switching views, but also when clicking today / prev / next?<br />
  I need to clear an array of unique event titles after (or before) each render is complete.</p>
  <p>So, similar to <code>eventAllRender</code> which was <a href="https://fullcalendar.io/docs/v4/upgrading-from-v3#event-rendering" rel="noreferrer">removed</a> starting v4.</p>
  <p>Currently using <code>.click</code> event for all buttons, which does the trick, but I was hoping there was something really linked to the actual rendering.</p>
  <pre><code>calendar.render();
  
  $('.fc-button').click( () =&gt; {
    console.log(&quot;do something&quot;)
  })
  </code></pre>