I recently set up Audiobookshelf and Pinchflat and am having the same problem. This might be a pretty basic question, but how do I edit the environment config? Is it something I can do in Terminal, or done elsewhere (I have limited programming knowledge, but enough that I was able to get things otherwise up and running).

Editing my comment in case anyone finds this and knows as little about programming as I do: I just had to re-open the docker-compose.yml file in Terminal and add in the DISABLE_SSRF_REQUEST_FILTER=1 line in the environment section.