This add-on allows users to prevent websites from using the some Javascript APIs to fingerprint them. Users can choose to block the APIs entirely on some or all websites (which may break some websites) or fake its fingerprinting-friendly readout API. More information on fingerprinting can be found at: The different block modes are: Protected "fingerprinting" APIs: Please report issues and feature requests at https://github.com/kkapsner/CanvasBlocker/issues