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filter is not described

register_meta_args filter-hook . WP 4.6.0

Filters the registration arguments when registering meta.


add_filter( 'register_meta_args', 'filter_function_name_9119', 10, 4 );
function filter_function_name_9119( $args, $defaults, $object_type, $meta_key ){
	// filter...

	return $args;
Array of meta registration arguments.
Array of default arguments.
Object type.
Meta key.

Where the hook is called

wp-includes/meta.php 1180
$args = apply_filters( 'register_meta_args', $args, $defaults, $object_type, $meta_key );

Where the hook is used (in WP core)

wp-includes/default-filters.php 99
add_filter( 'register_meta_args', '_wp_register_meta_args_whitelist', 10, 2 );