Add documentation & clarification to clone method #622

src/types/YXmlText.js

@@ -30,6 +30,10 @@ export class YXmlText extends YText {
   }
 
   /**
+   * Makes a copy of this data type that can be included somewhere else.
+   *
+   * Note that the content is only readable _after_ it has been included somewhere in the Ydoc.
+   *
    * @return {YXmlText}
    */
   clone () {