Whatsapp and FB Messenger are popular in Europe. Viber used to be but it is the number one messenger only in a few eastern countries now https://www.similarweb.com/blog/popular-messaging-apps-by-co...

I personally don't know anybody using it past early 2016. It's all Whatsapp, Messenger, Telegram (but many people don't know what it is) and Skype on the desktop. Snapchat among the kids.

it's also owned by FSB

What are you talking about? It's owned by Rakuten, a Japanese company.