How to see HTTP parameters and session data?

First, thanks for your work on better_errors!

Question: In my setup, better_errors seems to be working fine generally, but I don't see HTTP parameters and session data anywhere in its error pages. I suppose this is a setup misconfiguration on my side?

Background

To test-drive better_errors, I have a simple controller that intentionally raises an error.

Default Rails error page

The default Rails error page includes information such as HTTP parameters and session data:

better_errors error page

But better_errors only shows the following. Note that the Rack session section says #<ActionDispatch::Request::Session:0x1a2c0 not yet loaded>.

I do think better_errors is generally working as expected, the console is functional, etc.

Still, information such as _csrf_token, SERVER_NAME, HTTP_ACCEPT_LANGUAGE is missing.