Fix quick-key `Ctrl+D` (duplicate) not working

HISTORY.md

@@ -9,6 +9,7 @@ https://github.com/josdejong/jsoneditor
   Thanks @ziga-miklic.
 - Fixed JSONEditor not working when opened in a new window, see #1098.
   Thanks @joshkel.
+- Fix quick-key `Ctrl+D` (duplicate) not working.
 - Define "charset: utf-8" in all HTML examples.
 
 

src/js/Node.js

@@ -4555,7 +4555,7 @@ Node.onDuplicate = nodes => {
       if (clones[0].parent.type === 'object') {
         // when duplicating a single object property,
         // set focus to the field and keep the original field name
-        clones[0].dom.field.innerHTML = this._escapeHTML(nodes[0].field)
+        clones[0].dom.field.innerHTML = nodes[0]._escapeHTML(nodes[0].field)
         clones[0].focus('field')
       } else {
         clones[0].focus()