Keep in mind that most of the good features are Enterprise only. The Team version lacks any permission policy so everyone is able to invite, delete channels and so on. See pricing-feature-comparison. For this reason most projects I know and even the company I work for uses Rocket or Riot/Matrix.

@katarina You can use the mattermost CLI tool to export from your existing installation and then import to Cloudron installation. I have added the instructions to our docs here - https://cloudron.io/documentation/apps/mattermost/#migration

ahh, thanks very much! that makes sense