Safari can't open whatsapp://send?phone - how to fix it?

Question

safari

There is a link like:
WhatsApp
and it works fine under Mac in Chrome:


But not in Safari:

at first it seems to redirect from the address: https://wa.me/7910ХХХХХХХ to some intermediate one:

but then it drops out in whatsapp://send /?phone=7910ХХХХХХХ&text&source&data&app_absent with an error...

Do not offer to install WhatsApp on a Mac - it's clear that everything will work fine with it, the client just doesn't understand why there is such a problem with Safari...