Does what it needs to do within the limitations of what the new Firefox allows add-ons to do. I also like the full explanation of its working principle on the github readme page. Edit: People are complaining about bookmark permissions, but they're necessary for a gesture command to bookmark a page. See the add-on author's "Why Permissions Are Required" at the github wiki https://github.com/marklieberman/foxygestures/wiki/Why-Permissions-Are-Required