Hi Isaac, What you are describing is the [https://www.mozilla.org/en-US/firefox/features/add-ons/ add-on system for Firefox]. Mozilla has put out some great documentation about add-ons on their [https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons developer site] if you'd like to start writing your own extension. Or, if you're feeling adventurous, you may be able to contribute a feature directly to the browser. See the [https://firefox-source-docs.mozilla.org/contributing/contributing_to_mozilla.html contributing guide for developers] to get started.