Checklist

• Have you pulled and found the error with jc21/nginx-proxy-manager:latest docker image?
  ✔️
• Are you sure you're not using someone else's docker image?
  ✔️

Describe the bug

host.docker.internal is not resolved by nginx

To Reproduce

Steps to reproduce the behavior:

1. Run NPM
2. Run some web application on the Docker host (e.g. on port 5000)
3. Use host.docker.internal as target

4. Try to access the proxied host.docker.internal:5000
5. Target page is not displayed and error is logged

2019/12/15 19:47:17 [error] 998#998: *368 host.docker.internal could not be resolved (3: Host not found), client: 192.168.16.1, server: xxx.local.test, request: "GET / HTTP/2.0", host: "xxx.local.test", referrer: "http://localhost:81/nginx/proxy"

Expected behavior

The NPM proxied domain, should show the page running under 127.0.0.1 on the Docker host

Workaround

If I ping host.docker.internal on the running app container and use the resulting IP as target it works

Operating System

macOS