Grab hash from URL in html.Iframe

I would very much like to be able to grab the hash from the URL inside a html.Iframe in my app.

I have embed a website like this example:

Note the the hash in the end denotes which node a user has reached in the given decision tree hosted by Zingtree.

Can anyone point me in the right direction about how to follow the hash of such an URL in an embed website in a Dash app, please? :slightly_smiling_face: