I use respond.io unified chat/support system. This service merges the most polupar messenging platform into one single interface. It supports WhatsApp, Messenger, Line, Telegram, Viber, ...etc... and Gmail. Indeed, people can send emails to my Gmail address and I get them into the system as a chat. I already have my support form and would really like a button to conenct it to All-IN-chat. Thanks.