Comment by ghayes

Take a look at Firefox’s Fingerprinting Prevention feature. This includes a permission for canvas, as well as:

- Your timezone is reported to be UTC

- Not all fonts installed on your computer are available to webpages

- The browser window prefers to be set to a specific size

- Your browser reports a specific, common version number and operating system

- Your keyboard layout and language is disguised

- Your webcam and microphone capabilities are disguised

- The Media Statistics Web API reports misleading information

- Any Site-Specific Zoom settings are not applied

- The WebSpeech, Gamepad, Sensors, and Performance Web APIs are disabled

https://support.mozilla.org/en-US/kb/firefox-protection-agai...