How to force hide metaboxes on specific post type editor pages: RevSlider WPSEO by Yoast, whatever.

Force Hide Metaboxes on CPT Editor Page

The do_meta_boxes filter is run 3 times for every editor page load.  Once for each context.
So you only need to remove the metabox if you are in an editor you care about.

There are 3 parameters sent in the do_meta_boxes filter. So add the action this way:

`add_action( 'do_meta_boxes', 'remove_unwanted_metaboxes', 10, 3 );`

And then do something like this:

```
function remove_unwanted_metaboxes( $type, $context, $post ) {
	// This action will be executed for all context: normal, advanced and side
	// If you want to run it only for the normal context, you can.
	if ( 'normal' !== $context ) return; // Remove this line and it will check all contexts in case the box has been moved by user

	// get_current_screen() is defined on most admin pages, but not all.
	// The ones that don't have it won't have metaboxes we care about.
	if ( function_exists( 'get_current_screen' ) ) {  
		$curPostType = get_post_type();  // Get the current posttype
		$postTypesToCheck = array( 'posttype1', 'posttype2', 'page' );  // PostTypes hiding this metabox. This could be an object var from $this
		if ( in_array ( $curPostType, $postTypesToCheck ) ) {
			remove_meta_box( 'wpseo_meta', $curPostType, $context );
			remove_meta_box( 'postcustom', $curPostType, $context );
			remove_meta_box( 'rs-addon-typewriter-meta', $curPostType, $context );
			remove_meta_box( 'mymetabox_revslider_0', $curPostType, $context ); // Could add _1 _2 etc in case of multiple sliders per page
		}
	}
}
```