У вашего броузера проблема в совместимости с HTML5
How to install viber on System Linux Ubuntu 16.04 x32 & x64AMD :-
install Wine For Run Viber on x32BIT System :-
sudo add-apt-repository ppa:ubuntu-wine/ppa
sudo apt-get update
sudo apt-get install wine1.7 winetricks
install package Viber :-
wget http://download.cdn.viber.com/cdn/desktop/windows/ViberSetup.exe
wine ViberSetup.exe
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install on x64AMD System :-
wget download.cdn.viber.com/cdn/desktop/Linux/viber.deb
sudo apt-get install gdebi
sudo gdebi viber.deb
if not open Viber install libqt5gui5 and libgstreamer-plugins-base0.10-0
sudo apt-get install libqt5gui5
sudo apt-get install libgstreamer-plugins-base0.10-0
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