I am managing a WordPress network and would like to add the unfiltered_html user capability to the already predefined user role of Admin. In a standard installation of WordPress the Admin account would already have this capability but in an MU installation only Super Admins are afforded this capability. WordPress Roles and Capabilities.
How can I augment the Admin role from within a theme or plugin?
You can use WP_Role class,
So to address your original question about how to enable Admins to enter SCRIPT and IFRAME tags into post content, you’re looking for the ‘unfiltered_html’ capability, which in Multisite is only granted to Super Admins.
or you can run this once in your functions:
In order to allow another role other than Super Admin or Admin (depending if the WordPress installation is a network/MU instance or not) to add unfiltered html to a post or comment WordPressâ KSES filter must be removed.
Check if a user has a particular capability.
If so than remove KSES
This functionality is already wrapped up in unfiltered-mu, allowing admins and editors to add unfiltered html.