How to preview CryoCloud JupyterBook changes on CryoCloud JupyterHub?

[scottyhq]

The CryoCloud Jupyterbook contributing docs recommend previewing changes https://book.cryointhecloud.com/contributing/workflow.html#jupyterbook-preview

It would be great to be able to edit and preview the CryoCloud Jupyterbook from the CryoCloud JupyterHub, but it's unclear how to open the HTML generated after running jupyter-book build which outputs the following:

Finished generating HTML for book.
Your book's HTML pages are here:
    book/_build/html/
You can look at your book by opening this file in a browser:
    book/_build/html/index.html
Or paste this line directly into your browser bar:
    file:///tmp/jupyterbook-template/book/_build/html/index.html      

If I just double click on index.html I first have to click a trust HTML button and then I see this error message:

cc @yuvipanda who I suspect has an answer to this :)

[scottyhq]

I just learned that 'open in a new browser tab works'!

[mrsiegfried]

I just tried the open in new browser tab, but it gives me a 403... Did you find a work around for this?