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filter is not described

widget_(id_base)_instance filter-hook . WP 4.8.0

Filters the media widget instance prior to rendering the media.

Usage

add_filter( 'widget_(id_base)_instance', 'filter_function_name_1553', 10, 3 );
function filter_function_name_1553( $instance, $args, $this ){
	// filter...

	return $instance;
}
$instance(array)
Instance data.
$args(array)
Widget args.
$this(WP_Widget_Media)
Widget object.

Where the hook is called

WP_Widget_Media::widget()
wp-includes/widgets/class-wp-widget-media.php 244
$instance = apply_filters( "widget_{$this->id_base}_instance", $instance, $args, $this );

Where the hook is used (in WP core)

Does not used.