Since version 6.4.145 Group-Office can integrate with Rocket.Chat. With rocket chat you can chat with your team in different channels, share files and even start a video conference from your desktop, phone or tablet!
For installation see Rocket Chat in the system settings page.
To use Rocket.Chat install a client or use your browser and use the Rocket.Chat URL obtained from your system administrator. On the login screen press the “Login with Group-Office” button.