Uncaught SecurityError: Failed to read the 'contentDocument' property from 'HTMLIFrameElement': Sandbox access violation

[natea]

I'm trying to use the Google Instant Hangouts widget in an Open edX course, and the widget failed to load on the page when running on localhost. Looking at the Web Developer console in Chrome shows this error:

Refused to display 'https://talkgadget.google.com/u/0/talkgadget/_/widget?hangout_type=normal&p…431&parent=http%3A%2F%2Fpreview.localhost%3A8000&pfname=&rpctoken=12551397' in a frame because it set 'X-Frame-Options' to 'SAMEORIGIN'.
Uncaught SecurityError: Failed to read the 'contentDocument' property from 'HTMLIFrameElement': Sandbox access violation: Blocked a frame at "http://preview.localhost:8000" from accessing a frame at "null".  The frame being accessed is sandboxed and lacks the "allow-same-origin" flag.

It seems as though there's a cross-site scripting violation that is preventing Open edX from embedding the Hangouts widget in an iframe. Is there a workaround for this?

[robertomiranda]

I'm having the same issue, for some reason locally only works at 8080 port.

@zenorocha, @johncox-google, @jorr-at-google any idea how to put this work in another domain or port?

[patidarkeshav]

Uncaught DOMException: Failed to read the 'contentDocument' property from 'HTMLIFrameElement': Blocked a frame with origin "http://xyz.dev" from accessing a cross-origin frame.

Facing same issue on adding jquery.js