Rated 4 out of 5 stars

I love it. Really, I do. I just wish that it supported other colours, like red and green.

This review is for a previous version of the add-on (0.1.1). 

Version 0.2.0 supported red-green anaglyph.

In version 0.2.0 added support red-green anaglyph.
https://addons.mozilla.org/pl/firefox/addon/anaglyph-3d/versions/?page=1#version-0.2.0