Previewer

Enhancements to the node preview functionality in Drupal 9/10.

Currently it supports only previewing while editing nodes. But the idea is to support more preview functionality by abstracting, and offering, the same preview base functionality as the node module in drupal core does. While embedding this in the backend to see live changes while being on the node edit form.

What it does is using the preview route as a src for an iframe to show through the off canvas dialog. Altering the existing preview button to do an ajax submit and trigger the off canvas dialog. Making it possible to show it in your editing screen.

Also it refreshes your preview as long as it is open in the off canvas, by listening to the javascript "formUpdated" event that drupal core and many modules support when content is changed within the form.