Part 2 - Fixing one last glitch

Post.js

/* other imports */

import browser from 'bowser'; // the browser import

/* ... */

executeEnteringTransition = (node, done) => {
  this.postStyler.set({ ...this.from, visibility: 'visible' });

  const hidePreview = () => (this.preview.style.visibility = 'hidden');
  if (browser.safari) setImmediate(hidePreview);
  else hidePreview();
  
  /* same code */
}