Sounds like your a bit behind that times. Pale Moon 27 is a rebase from FF 38 which has WebRTC. I'm not sure why we should trust your claims, already shown misinformed, when the developer's page states something else. The PM community is basically in consensus in not wanting WebRTC.
As for external PDF readers I'd argue that avoiding the push for integrating or redeveloping more and more external applications into a browser is very sane.
rebase from FF 38 which has WebRTC
This is a bit like saying "Firefox 4 has HTML5". The WebRTC stack in Firefox evolved significantly from Firefox 38 to 50, as did the WebRTC standards themselves. That's why I pointed to interoperability issues.
Re:Feeling safer online with Firefox
by rebelwebmaster on Friday January 13, 2017 @01:57PM
(#13393564)
ESR38 stopped getting upstream security updates from Mozilla in April of 2016. But I'm sure the Palemoon folks have stayed on top of things since.
The real reason is that they are based off of an old ESR and their code wouldn't be able to inter-operate with anything else. Aside from the issue that they're not getting security patches for it, either...
The recommendation to use an external PDF reader is also not quite something I can stand behind. (Unless that external reader is Chrome...)