Although the author of this Add-On does not have any access to anything you do on your computer, this add-on does send information to Wikipedia or Wiktionary. Both these sites are generally pretty good about your privacy so you shouldn't have that much to worry about. If you are really worried, just take a look at the code: https://github.com/TheOtherRealm/InPageLookup Just thought I would state the obvious. Happy looking things up!