2013976 - When both CanvasRandomization/WebGLRandomization and EfficientRandomize RFPTargets are used, some randomization code does not run.

Status: ASSIGNED

(Core :: Privacy: Anti-Tracking, defect)

Description

[any1here]

Steps to reproduce:

Set ETP to Strict, then visit https://arkenfox.github.io/TZP/tests/canvasnoise.html and https://browserleaks.com/webgl.

Actual results:

getImageData is not being randomized on https://arkenfox.github.io/TZP/tests/canvasnoise.html.
WebGL image hash is not being randomized on https://browserleaks.com/webgl.

Expected results:

getImageData and WebGL image hash should show randomized values.

Comment 1

[any1here]

Attachment: Bug 2013976 - Ensure randomization code runs when both CanvasRandomization/WebGLRandomization and EfficientCanvasRandomization RFPTargets are enabled

Comment 2

[any1here]

Wasn't sure which version to use, so I used the earliest one where this regression occurred.

The regression was introduced with https://phabricator.services.mozilla.com/D267099 when ImageExtractionResult started returning ImageExtraction::EfficientRandomize, which prevents it from running the code that guards the randomization behind ImageExtraction::Randomize without providing an alternative.

Comment 3

[Tom Ritter [:tjr]]

I will review this, but am currently on leave, so it might take me a bit to find the time.