Thank you, that works. But why I cant upload plugins via GUI although I have set the right setting (https://screenshots.x-mailer.de/u/smichna-2020.09.15-1TsnjG54.png).

Hi @austinsonger is there anything in the app logs regarding that error?

thank you for your replies. I found the error in a complete different field. A custom emoji crashed the bulk export. After deleting this I could perform the export as planned and the import to Cloudron worked as described in the documentation. Still thank you for your efforts.

@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