See these threads to get confused:
- https://community.gitpod.io/t/cors-errors-due-to-new-gitpod-port-policy/4042/4
- https://community.gitpod.io/t/why-do-i-get-a-cors-error-but-only-if-my-port-is-private/5547/7
Note: Both the service (back-end) and app (front-end) servers are wrapped with nodemon, so any changes to the file will cause the server to refresh automatically.