diff --git a/inc/class-wp-revisions-control.php b/inc/class-wp-revisions-control.php
index d747f7ce6603a8c6463b424b30c9f7ad5173f0ca..a744fe337605c9cc2bac8f03fedeffec1c4a3f73 100644
--- a/inc/class-wp-revisions-control.php
+++ b/inc/class-wp-revisions-control.php
@@ -292,7 +292,10 @@ class WP_Revisions_Control {
 	 */
 	public function action_add_meta_boxes( $post_type, $post ) {
 		if (
-			use_block_editor_for_post( $post )
+			(
+				function_exists( 'use_block_editor_for_post' )
+				&& use_block_editor_for_post( $post )
+			)
 			|| ! post_type_supports( $post_type, 'revisions' )
 			|| 'auto-draft' === get_post_status()
 			|| count( wp_get_post_revisions( $post ) ) < 1