example.com address shown on Mattermost first-login flow
Today I signed up with your Mattermost server. The first time I logged in (that is, the first time I clicked "Sign in with Gitlab" here:)
It showed me a one-time message containing instructions to email email@example.com if anything went wrong. Probably there is a default set somewhere and you want to change it.
I unfortunately do not have a screenshot. It appears the message only appears once and to make it appear again I would have to make a second Heptapod account.