I just up upgraded to Mattermost 3.0.1, and everything is running apart from two things:
1) Mattermost doesn't pick up the old profile pictures (even though the folders are there). Reuploading them fixes this.
2) When I try to save settings in the system console I just get the error We received an unexpected status code from the server. (500). The config.json file (like everything else in the mattermost folder) is owned by mattermost:mattermost. So I don't think it's a file permission problem.
Any ideas?