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action is not described

begin_fetch_post_thumbnail_html action-hook . WP 2.9.0

Fires before fetching the post thumbnail HTML.

Provides "just in time" filtering of all filters in wp_get_attachment_image().

Usage

add_action( 'begin_fetch_post_thumbnail_html', 'action_function_name_9114', 10, 3 );
function action_function_name_9114( $post_id, $post_thumbnail_id, $size ){
	// action...
}
$post_id(int)
The post ID.
$post_thumbnail_id(int)
The post thumbnail ID.
$size(string|int[])
Requested image size. Can be any registered image size name, or an array of width and height values in pixels (in that order).

Changelog

Since 2.9.0 Introduced.

Where the hook is called

get_the_post_thumbnail()
begin_fetch_post_thumbnail_html
wp-includes/post-thumbnail-template.php 173
do_action( 'begin_fetch_post_thumbnail_html', $post->ID, $post_thumbnail_id, $size );

Where in WP core the hook is used WordPress

wp-includes/default-filters.php 435
add_action( 'begin_fetch_post_thumbnail_html', '_wp_post_thumbnail_class_filter_add' );