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filter is not described

widget_(id_base)_instance_schema filter-hook . WP 4.9.0

Filters the media widget instance schema to add additional properties.

Usage

add_filter( 'widget_(id_base)_instance_schema', 'filter_function_name_681', 10, 2 );
function filter_function_name_681( $schema, $this ){
	// filter...

	return $schema;
}
$schema(array)
Instance schema.
$this(WP_Widget_Media)
Widget object.

Where the hook is called

WP_Widget_Media::get_instance_schema()
widget_(id_base)_instance_schema
WP_Widget_Media_Gallery::get_instance_schema()
widget_(id_base)_instance_schema
wp-includes/widgets/class-wp-widget-media.php 161
$schema = apply_filters( "widget_{$this->id_base}_instance_schema", $schema, $this );
wp-includes/widgets/class-wp-widget-media-gallery.php 92
$schema = apply_filters( "widget_{$this->id_base}_instance_schema", $schema, $this );

Where the hook is used (in WP core)

Does not used.