diff --git a/src/wp-admin/includes/post.php b/src/wp-admin/includes/post.php
index 8eab849f4e..a2bbd8753e 100644
--- a/src/wp-admin/includes/post.php
+++ b/src/wp-admin/includes/post.php
@@ -2218,36 +2218,22 @@ function the_block_editor_meta_box_post_form_hidden_fields( $post ) {
 	 * Some meta boxes hook into these actions to add hidden input fields in the classic post form. For backwards
 	 * compatibility, we can capture the output from these actions, and extract the hidden input fields.
 	 */
-	$actions = array(
-		'edit_form_after_title',
-		'edit_form_advanced',
-	);
-
-	foreach ( $actions as $action ) {
-		ob_start();
-		do_action_deprecated(
-			$action,
-			array( $post ),
-			'5.0.0',
-			'block_editor_meta_box_hidden_fields',
-			__( 'This action is still supported in the classic editor, but is deprecated in the block editor.' )
-		);
-		$classic_output = ob_get_clean();
-
-		if ( ! $classic_output ) {
+	ob_start();
+	/** This filter is documented in wp-admin/edit-form-advanced.php */
+	do_action( 'edit_form_after_title', $post );
+	/** This filter is documented in wp-admin/edit-form-advanced.php */
+	do_action( 'edit_form_advanced', $post );
+	$classic_output = ob_get_clean();
+
+	$classic_elements = wp_html_split( $classic_output );
+	$hidden_inputs    = '';
+	foreach( $classic_elements as $element ) {
+		if ( 0 !== strpos( $element, '<input ') ) {
 			continue;
 		}
 
-		$classic_elements = wp_html_split( $classic_output );
-		$hidden_inputs    = '';
-		foreach( $classic_elements as $element ) {
-			if ( 0 !== strpos( $element, '<input ') ) {
-				continue;
-			}
-
-			if ( preg_match( '/\stype=[\'"]hidden[\'"]\s/', $element ) ) {
-				echo $element;
-			}
+		if ( preg_match( '/\stype=[\'"]hidden[\'"]\s/', $element ) ) {
+			echo $element;
 		}
 	}
 	?>