The Download Now link will prompt a local download of the Firefox extension. To install the extension directly, open the file using your Firefox browser.
From Gomita:
FireGestures is a customizable mouse gestures extension which enables to execute various commands and user scripts with five types of gestures. You can execute various commands and user scripts with five types of mouse gestures like mouse gestures, wheel gestures, rocker gestures, key press gestures, and tab wheel gestures.
