Pale Moon

Pale Moon is a free, open-source web browser built on its own maintained platform and rendering engine, Goanna, which is a derivative of Gecko. The vendor describes it as a true fork with ancestral roots in Mozilla Firefox and as a totally independent product. It offers customization options for navigation controls and the tab strip, full theming, and add-ons written in XUL. It is compatible with many legacy Firefox extensions, with support depending on the community.