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filter is not described

allowed_block_types filter-hook . WP 5.0.0

Filters the allowed block types for the editor, defaulting to true (all block types supported).

Usage

add_filter( 'allowed_block_types', 'filter_function_name_4024', 10, 2 );
function filter_function_name_4024( $allowed_block_types, $post ){
	// filter...

	return $allowed_block_types;
}
$allowed_block_types(true/false/array)
Array of block type slugs, or boolean to enable/disable all.
$post(object)
The post resource data.

Where the hook is called

In file: /wp-admin/edit-form-blocks.php
allowed_block_types
wp-admin/edit-form-blocks.php 151
$allowed_block_types = apply_filters( 'allowed_block_types', true, $post );

Where the hook is used (in WP core)

Does not used.