ImageTweak user guide - GitHub. ImageTweak is open source under the GPLv3, feel free to hack on the source code and send patches or pull requests. Found a bug? See Troubleshooting. If you like ImageTweak please consider donating via mozilla.org or by sending bitcoins to 1265ciMoFwnX4y4gGxXNGkiD7Qu24oYSqw. Status of this document. Your Account. My Account.