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action is not described

dynamic_sidebar_after action-hook . WP 3.9.0

Fires after widgets are rendered in a dynamic sidebar.

Note: The action also fires for empty sidebars, and on both the front end and back end, including the Inactive Widgets sidebar on the Widgets screen.

Usage

add_action( 'dynamic_sidebar_after', 'action_function_name_8704', 10, 2 );
function action_function_name_8704( $index, $has_widgets ){
	// action...
}
$index(int/string)
Index, name, or ID of the dynamic sidebar.
$has_widgets(true/false)
Whether the sidebar is populated with widgets.
Default: true

Where the hook is called

dynamic_sidebar()
wp-includes/widgets.php 760
do_action( 'dynamic_sidebar_after', $index, true );
wp-includes/widgets.php 638
do_action( 'dynamic_sidebar_after',  $index, false );

Where the hook is used (in WP core)

wp-includes/class-wp-customize-widgets.php 1585
add_action( 'dynamic_sidebar_after', array( $this, 'end_dynamic_sidebar' ) );