But it can happen on any platform. Not only on WhatsApp. No mistake on WhatsApp’s side.

Yeah, Chromium is not proprietary. It is a free and open-source software project developed and maintained by Google.

But vivaldi is absolutely proprietary as it’s not open-source.

You can choose brave or firefox. Or maybe you are not too much privacy concious then vivaldi also a good choice. I think these are better than using other browsers from outside store. Maybe thats too a reason why iphone is so smooth and fast.