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action is not described

add_tag_form_fields action-hook . WP 3.0.0

Fires after the Add Tag form fields for non-hierarchical taxonomies.

Usage

add_action( 'add_tag_form_fields', 'action_function_name_2783' );
function action_function_name_2783( $taxonomy ){
	// action...
}
$taxonomy(string)
The taxonomy slug.

Where the hook is called

In file: /wp-admin/edit-tags.php
add_tag_form_fields
wp-admin/edit-tags.php 463
do_action( 'add_tag_form_fields', $taxonomy );

Where the hook is used (in WP core)

Does not used.