Content preview

With help of All Entity Preview it is possible to preview the changes to the content before it is saved. To enable preview (available since version 1.5.0) functionality get the module with composer:

composer require 'drupal/all_entity_preview:^1.0@alpha'

Install as usual. Configure what entity types and bundle are allowed to be previewed on module's configuration page here /admin/config/content/preview

If you want the preview be automatic as you do the changes in sidebar form, enable "Automatic preview" here /admin/config/frontend-editing, it can be always enabled/disabled on the form itself:

To see preview feature in action, check the Youtube video