With `docker-compose`, see the `Proxy support example` in <ahref="https://github.com/dgtlmoon/changedetection.io/blob/master/docker-compose.yml">docker-compose.yml</a>.
For more information see https://docs.python-requests.org/en/master/user/advanced/#proxies
This proxy support also extends to the notifications https://github.com/caronc/apprise/issues/387#issuecomment-841718867
See the wiki https://github.com/dgtlmoon/changedetection.io/wiki/Proxy-configuration