Error with Discourse Comments Integration

Trying to get setup with Discourse comments on my site and I got super far, but now am encountering the following error -

Failed to execute 'postMessage' on 'DOMWindow': The target origin provided ('https://forum.mysticspeech.com') does not match the recipient window's origin ('https://mysticspeech.com').

Running latest version of Ghost on Bitnami install (Ubuntu). Followed the Ghost integration docs on this exactly. Anyone else encounter this before?