You should point the proxy at a Remix route and not the server, so, for example:
app/routes folder:
app.api.jsx
Then the App Proxy URL would be:
[https://mydomain.trycloudflare.com/app/api](https://mydomain.trycoludflare.com/app)
Then your fetch() URL would be like:
/subpath_prefix/subpath
Which would actually be:
/apps/api
Note that, you don’t have to add the domain part of the URL, in the fetch() URL param.
Please remember that form POST requests, hit the:
Remix action() method
And GET requests, hit the:
Remix loader() method