followed manual.seafile.com/docker/deploy_seafile_with_docker/ to install Docker and Seafile firstly on Ubuntu 20.04 LTS. Seafile can be successfully up by Docker with docker-compose up -d, but seafile.example.com couldn’t by found by Firefox. Checked Firewall not installed.
This is an example domain. You should change it to your own domain or IP address.
Yes!! Thanks!