Failed to load widget Elixir Livebook in private space


I am currently playing around a bit with Elixir Livebooks and try to make a Kino control to download output generated in that Livebook. However, this seems to fail in a private space:

Failed to load the widget JS module, got the following error:

    error loading dynamically imported module:

See the browser console for more details. If running behind an authentication proxy, make sure the /public/* routes are publicly accessible.

Note the reference to public in the error message.

Is there something that I can do to resolve this, or is Livebook just not supported completely if ran in a private space? For completeness, I can trigger this problem with this code in an Elixir Livebook:

  {:kino, "~> 0.12.3"}
]) -> "hello" end)