Pale Moon is an open-source web browser based on Firefox focusing on efficiency and ease of use. It features support for full themes (total freedom over any element's design), support for easily-created lightweight themes (skins), smooth and speedy page drawing and script processing, support for many Firefox extensions, support for HTML5 and CSS3, and more.
Pale Moon is fast, has the good (pre-Australis) UI and runs the Firefox addons I need.
I've used Pale Moon now for many years and I never look back to Firefox. Pale Moon is a fast, stable and customizable OpenSource browser with security options which other browsers didn't have (like the intern XSS filter). From my side, I highly recommend Pale Moon!
Pale Moon on my computer was crashing a lot. Version 25 did not work with many of the Firefox add-ons that I had used before.Used to be good, but not anymore. Will look for a new alternative to Firefox.