Gitlab url is not correct if I use Nginx proxy with custom https port

Here is my docker-compose file content (I have skipped some configs since they are not relevant):

version: '2'

services:
  gitlab:
    restart: unless-stopped
    image: sameersbn/gitlab:17.3.3
    container_name: gitlab
    ports:
    - "20080:80"
    - "20443:443"
    - "10022:22"
    environment:
    - GITLAB_HTTPS=true
    - SSL_SELF_SIGNED=false
    - NGINX_X_FORWARDED_PROTO=https

    - GITLAB_HOST=gitlab.example.com
    - GITLAB_PORT=10443
    - GITLAB_SSH_PORT=10022
    - GITLAB_RELATIVE_URL_ROOT=

And I use Nginx Proxy Manager to proxy gitlab, here is my config:

Proxy host name: gitlab.example.com
Scheme: http
Forward Hostname / IP: 192.168.1.105(my gitlab container's IP)
Forward Port: 20080
SSL Certificate: enabled
HTTP/2 Support: enabled

When I turn on the proxy, I can visit gitlab through https://gitlab.example.com:10443, but in gitlab's frontend page, it shows the incorrect url, for example, the Admin page button's url is https://gitlab.example.com, and every time I try to login into Gitlab, it redirect me to https://gitlab.example.com/users/sign_in, instead of https://gitlab.example.com:10443/users/sign_in, that's quite annoying.

Is there any problem with my config?

Start with the supplied docker-compose settings and the Nginx Proxy Manager proxy configuration, focusing on how the external HTTPS port 10443 is communicated to GitLab. Reproduce the redirect and inspect the generated frontend URLs; done means login and Admin links retain https://gitlab.example.com:10443.