Give Author users the right to embed

I’m trying to allow “author” users to embed in posts. I (the administrator) can iframe, embed, etc…., but authors can not.

Can someone show me to give authors ‘just’ the ability to embed and iframe in posts?

The capability you are after is called unfiltered_html. Some options:

1. Modify author capabilities in your theme functions.php. This is saved in the DB, so you can access a page, make sure it works then remove it from your functions.php file. A better option would be to run it on theme activation. See this page on WP Codex for options:

   function add_theme_caps() {
       // gets the author role
       $role = get_role( 'author' );
   
       // This only works, because it accesses the class instance.
       // would allow the author to edit others' posts for current theme only
       $role->add_cap( 'unfiltered_html' ); 
   }
   add_action( 'admin_init', 'add_theme_caps');
   

2. Use a plugin that allows you to modify it using a UI, like User Role Editor.