UserAgent: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36
Platform: 9582.0.0

Steps to reproduce the problem:
1. Download a html page remotely and save in persistent local storage. I used pnacl APIs and C libraries to do so but this however to reproduce this a more simpler approach can be used using XHR requests
2. chrome.app.window.create('chrome-extension://<app id>/persistent/<directories>/index.html');
3. Window fails to open with a Unchecked runtime.lastError while running app.window.create: the URL used for window creation must be local for security reasons.

What is the expected behavior?
Expected that a new app window is opened using the index.html loaded from persistent local storage.

What went wrong?
Unchecked runtime.lastError while running app.window.create: the URL used for window creation must be local for security reasons.

Did this work before? No 

Does this work in other browsers? Yes

Chrome version: 60.0.3107.0  Channel: dev
OS Version: Google_Zako.5219.30.0
Flash Version: 26.0.0.110

I have a client with many chromeboxes and I am developing a cms app which has a business model restricting me to download html pages (with js) periodically and load them inside an app. I have also attempted to use webview/iframes which also did not work. Is it possible to enable urls pointing to persistent local storage by adding more permissions to the manifest.json?