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filter is not described

heartbeat_send filter-hook . WP 3.6.0

Filters the Heartbeat response sent.

Usage

add_filter( 'heartbeat_send', 'filter_function_name_5007', 10, 2 );
function filter_function_name_5007( $response, $screen_id ){
	// filter...

	return $response;
}
$response(array)
The Heartbeat response.
$screen_id(string)
The screen id.

Where the hook is called

wp_ajax_heartbeat()
heartbeat_send
wp-admin/includes/ajax-actions.php 2831
$response = apply_filters( 'heartbeat_send', $response, $screen_id );

Where the hook is used (in WP core)

wp-includes/default-filters.php 407
add_filter( 'heartbeat_send', 'wp_auth_check' );