nvm use 18
yarn
yarn run serve

Sending a POST request with any body to /test will trigger the Response body object should not be disturbed or locked TypeError.

> curl -X POST -H 'Content-Type: application/json' -d '{"message":"hello"}' FIREBASE_URL/api/test

The problem persists if you use c.req.raw() to get the unwrapped Request object and cloning it with Request.clone().

> curl -X POST -H 'Content-Type: application/json' -d '{"message":"hello"}' FIREBASE_URL/api/raw