"Not allowed to use restricted network port" (WebKitErrorDomain:103)

In my Server(CentOS 7.9) I running a docker container.

[root@att ~]# docker ps 
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS                    NAMES
028fe4b64697        training/webapp     "python app.py"     21 minutes ago      Up 21 minutes       0.0.0.0:6000->5000/tcp

this is a web page.

I can in my local macOS wget the page:

wget remote_ip:6000

and get the index.html, but I can not access in Browser, it report error:

The Safari browser cannot open the page "http://demo.com:6000/". The error is: "Not allowed to use restricted network port" (WebKitErrorDomain:103)