Clear the UndoManager on `loaded` event

src/editor/index.js

@@ -571,6 +571,7 @@ module.exports = config => {
       // Do post render stuff after the iframe is loaded otherwise it'll
       // be empty during tests
       em.on('loaded', () => {
+        this.UndoManager.clear();
         em.get('modules').forEach(module => {
           module.postRender && module.postRender(editorView);
         });

src/editor/model/Editor.js

@@ -88,11 +88,10 @@ module.exports = Backbone.Model.extend({
       module.onLoad();
     });
 
-    // Stuff to do post load (eg. init undo manager for loaded components)
+    // Stuff to do post load
     const postLoad = () => {
-      this.get('modules').forEach(module =>
-        module.postLoad && module.postLoad(this)
-      );
+      const modules = this.get('modules');
+      modules.forEach(module => module.postLoad && module.postLoad(this));
       clb && clb();
     };
 

src/undo_manager/index.js

@@ -1,5 +1,5 @@
 /**
- * This module allows to manage the stack of changes applied on canvas
+ * This module allows to manage the stack of changes applied in canvas
  *
  * You can access the module in this way
  * ```js