@isabella11 said:
I am using this extension and works great from my side. I don't know why people say it's not working but I've downloaded this from opera and using it since a month. No problem at all as I am amazon assistant it really helps me. I've also download WhatsApp from it also works fine. You can also download it from here: https://addons.opera.com/en/extensions/details/whatsapp-in-opera/
Thanks it is working pretty fine