Some of those are for optional features like WebRTC, they are not all needed for a functional browser.
Re:Haiku OS ported and running on RISC-V
by codetrotter on Wednesday May 12, 2021 @06:15PM
(#27135810)
This thread is about fully featured browsers though. I think without WebRTC you can not call the browser fully featured.
https://github.com/NetBSD/pkgsrc/tree/trunk/www/firefox/patc...