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filter is not described

upload_mimes filter-hook . WP 2.0.0

Filters list of allowed mime types and file extensions.

Usage

add_filter( 'upload_mimes', 'filter_function_name_3968', 10, 2 );
function filter_function_name_3968( $t, $user ){
	// filter...

	return $t;
}
$t(array)
Mime types keyed by the file extension regex corresponding to those types.
$user(int/WP_User/null)
User ID, User object or null if not provided (indicates current user).

Changelog

Since 2.0.0 Introduced.

Where the hook is called

get_allowed_mime_types()
upload_mimes
wp-includes/functions.php 3190
return apply_filters( 'upload_mimes', $t, $user );

Where in WP core the hook is used

wp-includes/ms-default-filters.php 97
add_filter( 'upload_mimes', 'check_upload_mimes' );