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function register_block_core_footnotes_post_meta() {
	$post_types = get_post_types( array( 'show_in_rest' => true ) );
	foreach ( $post_types as $post_type ) {
		// Only register the meta field if the post type supports the editor, custom fields, and revisions.
		if (
			post_type_supports( $post_type, 'editor' ) &&
			post_type_supports( $post_type, 'custom-fields' ) &&
			post_type_supports( $post_type, 'revisions' )
		) {
			register_post_meta(
				$post_type,
				'footnotes',
				array(
					'show_in_rest'      => true,
					'single'            => true,
					'type'              => 'string',
					'revisions_enabled' => true,
				)
			);
		}
	}
}