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How to automatically block Canvas?

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Some of the Support-Members here already know im using privacy.resistFingerprinting - true. Now, each time im visiting a website im being asked to block or allow fingerprinting. How can i set this so it will always auto-block canvas?

-see attached screenshot

Some of the Support-Members here already know im using privacy.resistFingerprinting - true. Now, each time im visiting a website im being asked to block or allow fingerprinting. How can i set this so it will always auto-block canvas? -see attached screenshot
Sarin'efijery napaingotra

Vahaolana nofidina

Canvasblocker is more advanced than firefox's inbuilt protection, with domrect protection, audio api protection, and more on top of canvas protection. It also has settings which can change how it protects you, as opposed to Firefox's binary option. Full list of tests is at the canvasblocker test page.

It is correct that privacy.resistFingerprinting is ok, I have experienced graphical issues with canvas apps when it is on. It also can make your fingerprint not change in the way that Canvasblocker allows you to do.

You do not notice when Firefox blocks it normally, it only asks when a user interaction happens with the canvas.

Hamaky an'ity valiny ity @ sehatra 👍 1

All Replies (4)

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Hello,

When it comes to preventing canvas-based fingerprinting, Firefox does well, but causes websites to break. I suggest Canvasblocker, an addon that randomizes outputs and protects many javascript apis, including newer sound based attacks. To use Canvasblocker effectively, privacy.resistFingerprinting should be set to false, as it interferes.

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andmagdo said

Hello, When it comes to preventing canvas-based fingerprinting, Firefox does well, but causes websites to break. I suggest Canvasblocker, an addon that randomizes outputs and protects many javascript apis, including newer sound based attacks. To use Canvasblocker effectively, privacy.resistFingerprinting should be set to false, as it interferes.

So you recommend Canvasblocker over privacy.resistFingerprinting. This one? https://addons.mozilla.org/en-US/firefox/addon/canvasblocker/ I read the description, they say it's ok to have privacy.resistFingerprinting true.

But i dont understand, why would this addon be better as the built-in option from firefox? Also, that means there is no way to auto-block canvas? firefox always asks me about it, instead of by default just blocking it, that's wired.

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Vahaolana Nofidina

Canvasblocker is more advanced than firefox's inbuilt protection, with domrect protection, audio api protection, and more on top of canvas protection. It also has settings which can change how it protects you, as opposed to Firefox's binary option. Full list of tests is at the canvasblocker test page.

It is correct that privacy.resistFingerprinting is ok, I have experienced graphical issues with canvas apps when it is on. It also can make your fingerprint not change in the way that Canvasblocker allows you to do.

You do not notice when Firefox blocks it normally, it only asks when a user interaction happens with the canvas.

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andmagdo said

Canvasblocker is more advanced than firefox's inbuilt protection, with domrect protection, audio api protection, and more on top of canvas protection. It also has settings which can change how it protects you, as opposed to Firefox's binary option. Full list of tests is at the canvasblocker test page. It is correct that privacy.resistFingerprinting is ok, I have experienced graphical issues with canvas apps when it is on. It also can make your fingerprint not change in the way that Canvasblocker allows you to do. You do not notice when Firefox blocks it normally, it only asks when a user interaction happens with the canvas.

Thank you again, will install canvas blocker and disable built in resist fingerprinting.