You can disable your Android device screen, if you don’t like having it turning on every single time you receive a new Viber notification. When this is done, any new incoming messages will no longer light up your device screen automatically. In order to turn off light screen for messages, click on Navicon located at the bottom right and elect SETTINGS and then click on Notifications and uncheck Light screen for messages.
Extra Tip: Turn off Notifications
There is always a specific period of the day when you want to avoid getting messages from Viber, most especially when you are busy at work. In this case, switch the notifications off from inside the Viber app and you are good to go.