frappe_docker/docs/connect-to-localhost-services-from-containers-for-local-app-development.md

Not using separate container
Add following to frappe container from the `.devcontainer/docker-compose.yml`:

```yaml
extra_hosts:
  app1.localhost: 172.17.0.1
  app2.localhost: 172.17.0.1
```

This is makes the domain names `app1.localhost` and `app2.localhost` connect to docker host and connect to services running on `localhost`.