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filter is not described

post_gallery filter-hook . WP 2.5.0

Filters the default gallery shortcode output.

If the filtered output isn't empty, it will be used instead of generating the default gallery template.

Usage

add_filter( 'post_gallery', 'filter_function_name_373', 10, 3 );
function filter_function_name_373( $output, $attr, $instance ){
	// filter...

	return $output;
}
$output(string)
The gallery output.
Default: ''
$attr(array)
Attributes of the gallery shortcode.
$instance(int)
Unique numeric ID of this gallery shortcode instance.

Changelog

Since 2.5.0 Introduced.
Since 4.2.0 The $instance parameter was added.

Where the hook is called

gallery_shortcode()
post_gallery
wp-includes/media.php 1707
$output = apply_filters( 'post_gallery', '', $attr, $instance );

Where the hook is used (in WP core)

Usage not found!