It can be anything! An apex, subdomain, or even a URL.
Results for*.slack-files.com.slack.testslack.proxyqa.myshn.eu
www.*.slack-files.com.slack.testslack.proxyqa.myshn.euslack-files.com.slack.testslack.proxyqa.myshn.eucom.slack.testslack.proxyqa.myshn.euslack.testslack.proxyqa.myshn.eutestslack.proxyqa.myshn.euproxyqa.myshn.eumyshn.eueu