Fix communication with sandbox after a fork

Author: CompuIves

packages/app/src/app/components/Preview/index.js

@@ -1,7 +1,7 @@
 // @flow
 import * as React from 'react';
 import type { Sandbox, Module } from 'common/types';
-import { listen, dispatch, registerFrame } from 'codesandbox-api';
+import { listen, dispatch, registerFrame, resetState } from 'codesandbox-api';
 import { debounce } from 'lodash-es';
 import io from 'socket.io-client';
 
@@ -334,6 +334,8 @@ class BasePreview extends React.Component<Props, State> {
   handleSandboxChange = (newId: string) => {
     this.serverPreview = getTemplate(this.props.sandbox.template).isServer;
 
+    resetState();
+
     const url = this.serverPreview
       ? getSSEUrl(newId)
       : frameUrl(newId, this.props.initialPath || '');

packages/codesandbox-api/src/dispatcher/index.ts

@@ -19,6 +19,11 @@ const parentOriginListener = (e: MessageEvent) => {
 
 self.addEventListener('message', parentOriginListener);
 
+export function resetState() {
+  parentOrigin = null;
+  bundlers.clear();
+}
+
 /**
  * Send a message to the editor, this is most probably an action you generated
  *