Canvasblocker: Some Canvas spoofing measures can be detected

[ghost]

There is a new study on detecting fingerprinting countermeasures. It also shows flaws with state of the art canvas spoofing. I'm not sure if this addon is affected, but maybe it is what they mean by "CANVAS FP BLOCK".
https://hal.inria.fr/hal-01820197/document
Especially relevant are the parts

4.1.4 Checking Canvas Poisoning
4.2.3 Analyzing the Detected Countermeasures

[Thorin-Oakenpants]

@tzimon the part you want to read from Antoine Vastel is https://antoinevastel.com/tracking/2018/07/01/eval-canvasdef.html

See https://github.com/ghacksuserjs/ghacks-user.js/issues/458 for our discussion. CB is not affected

[kkapsner]

I would not say CB is not affected at all (it does change the colors so it might trigger the color statistics flag - but we have the "ignore most frequent colors" setting which should reduce the risk), but for the most parts it should be fine.

[kkapsner]

I dug deeper and found a way to detect that CB altered the functions... the fix is almost finished and I will release the next version soon.

[kkapsner]

The new release is out.