--- a/src/formats/xhtml.js	Sat Aug 13 22:37:46 2022 -0600
+++ b/src/formats/xhtml.js	Sun Aug 14 20:36:17 2022 -0600
@@ -21,6 +21,7 @@
 	var removeAttr = dom.removeAttr;
 	var convertElement = dom.convertElement;
 	var extend = utils.extend;
+	var extendDeep = utils.extendDeep;
 	var each = utils.each;
 	var isEmptyObject = utils.isEmptyObject;
 
@@ -524,8 +525,7 @@
 				);
 			}
 
-			editor.commands = extend(true,
-				{}, defaultCommandsOverrides, editor.commands);
+			editor.commands = extendDeep({}, defaultCommandsOverrides, editor.commands);
 		};
 
 		/**