General knowledge: Once installed, an app is typically stored in the /Applications directory, and the user preferences for how the app is configured are stored in ~/Library/Preferences directory. If you have no clue how to do it right, or have difficulty in getting rid of Mozilla Firefox Developer Edition, the removal solutions provided in the post could be helpful. This page is about how to properly and thoroughly uninstall Mozilla Firefox Developer Edition from Mac. Removing applications on Mac is pretty straightforward for experienced users yet may be unfamiliar to newbies. Perfect Solutions to Uninstall Mozilla Firefox Developer Edition for Mac