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filter is not described

excerpt_allowed_blocks filter-hook . WP 4.4.0

Filters the list of blocks that can contribute to the excerpt.

If a dynamic block is added to this list, it must not generate another excerpt, as this will cause an infinite loop to occur.

Usage

add_filter( 'excerpt_allowed_blocks', 'filter_function_name_9210' );
function filter_function_name_9210( $allowed_blocks ){
	// filter...

	return $allowed_blocks;
}
$allowed_blocks(array)
The list of allowed blocks.

Where the hook is called

excerpt_remove_blocks()
wp-includes/blocks.php 154
$allowed_blocks = apply_filters( 'excerpt_allowed_blocks', $allowed_blocks );

Where the hook is used (in WP core)

Does not used.