Rocket Chat Official App

Place this app in nextcloud/apps/

Not tested yet with 4.8.x and 5.x.x

Rocket Chat Configuration

If you get something like "refused to connect" and/or "ERR_BLOCKED_BY_RESPONSE" then you need to go to "Administration -> General -> Options to X-Frame-Options" and add your Nextcloud URL e.g. https://rgwit.mydomain.com
In order to add members to a chat about a file directly from the discussion view an admin must go to "Administration -> Layout -> User Interface" and check "Show top navbar in embedded layout"
To be able to register users and get an auth token, your RocketChat server MUST have the Environment Variable "CREATE_TOKENS_FOR_USERS=true" set. In a standard installation, just add it (without double quotes, for sure) in /lib/systemd/system/rocketchat.service
UPDATE SINCE 4.8.x The user that will authenticate in the NextCloud MUST HAVE THE ROLE OF BOT!

As an NextCloud admin go to "Settings -> Administration -> Rocket Chat"
Provide the Rocket Chat installation URL, Admin user name and Password and Click Connect and Register

While using NextCloud you can receive notifications from Rocket chat by allowing the browser to send desktop notifications.