There is no doubt that the Mozilla Firefox browser enjoys great acceptance thanks to the high level of configuration that the program allows its users and the endless list of extensions, which serve to improve and increase the service of said browser.
As it could not be otherwise, there are also skins to change the visual aspect of the program, and this OldFactory Black is one of them, because this skin changes the usual aspect of Mozilla Firefox until leaving it black with buttons that remember the style of the old factories (hence the name).
So your Mozilla will have a completely original appearance (works only for Mozilla Firefox 2.0).
You can free download OldFactory Black 32, 64 bit and safe install the latest trial or new full version for Windows 10 from the official site.