Most of the browser privacy features that I see being implemented across browsers (Firefox, Chrome, Brave, Safari) are little more than privacy theatre with unclear end goals. If they want to hide that Incognito is being used, they should state that and publish a design document.
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A nice example is Safari hiding WEBGL_debug_renderer_info to supposedly mitigate hardware fingerprinting distinguishing between Apple devices. I don't see how that's actually supposed to work. This applies to a huge portion of the privacy mitigations in browsers and extensions.
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Instead of aiming to provide fundamental privacy improvements, browsers are primarily shipping mitigations for specific code being used in the wild. They target the lowest common denominator of tracking. Safari at least has some actual substance with Chromium starting to copy it.
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Mitigations should not simply be aiming to make adversaries rewrite their code and cope with minor annoyances and barriers. They should have clear threat models / goals, aiming to provide some fundamental improvement that can actually be quantified and explained in documentation.
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Hm, I'm clearly not an expert in computer security, but as far as I can see that model needs to incorporate a lot of stochastic aspects, in which case all but very few mitigations (e.g. air-gapping) are mostly barriers, just with varying likelihood of getting surmounted.
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If the benefits of a mitigation cannot be quantified, that doesn't sound useful. Privacy and security features need to be designed with a clear threat model and goals from the start. If they simply break existing malicious code the burden being created is really on the defenders.
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Chromium added substantial complexity to try to remove one of the widely used methods to detect Incognito mode. It doesn't work and the goals are unclear. The only thing that has been accomplished is forcing the adversaries to update their library for detecting Incognito mode.
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If they commit to making this a property of Incognito mode and actually come up with a plan, that would be a different story. It wouldn't look like this. It doesn't make sense to take action without having a threat model and a plan to address it. It's harmful rather than helpful.
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The mitigation was widely reported in the media, and users now have the impression this is a property that Incognito is meant to provide, despite the project not being committed to it. The attitude was it would be nice to have and why not do something without thinking too much.
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I'm not aware of the formal documentation (if it exists) about what properties incognito mode should have, but its name does imply that "mitigating user identification" is clearly among them. Somewhere up top.
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Preventing detection of Incognito mode isn't something that they're committed to providing. It isn't a current design goal of Incognito mode. Do you see the problem with giving people the impression that it is, when it doesn't provide it and they aren't committed to doing that?