H5P Resize Event

h5presize.js

/* Wait for DOM to load */
document.addEventListener('DOMContentLoaded', function() {
  /* Add event listener to TOC links */
  const buttons = document.querySelectorAll('.chapter-title'); 
  buttons.forEach(function(button) {
    button.addEventListener('click', function () {
      // Need a timeout to wait for the active page getting the correct class
      setTimeout(function() {
        const iframes = document.querySelectorAll('iframe');
        iframes.forEach(function(iframe) {
          if (iframe.src.indexOf('h5p') !== -1) {
            iframe.contentWindow.postMessage({context: 'h5p', action: 'ready'}, '*');
          }
        })
      }, 300);
    });
  });
});