Threema
No native desktop apps available yet, but there is a web version for your browser. No phone number is required to signup but there is a payment involved to get the app.…
Web Messaging
The Messaging we recommend, filtered to Web. See all Messaging →
Brave Talk
The person creating the call requires to use Brave Browser, but the participants can join from any browser.
Jitsi Meet
Desktop version downloads can be found here .
Stoat
Open source, self-hostable Discord alternative, formerly Revolt. Built for communities that want off Discord, but it is not end-to-end encrypted.