Re: [mediacapture-image] Deny mandatory PTZ contraints in basic getUserMedia contraints (#261)

Allowing required constraints in advanced sets has the same fingerprinting consequences as allowing them in the basic set.
If they were allowed in the basic set:
getUserMedia({video: {pan: {exact: 10}}) gives OverconstrainedError if pan is not supported, which is a fingerprinting issue.

Similarly, with advanced constraints and assuming 10 is never a default width,
getUserMedia({video: advanced: [{pan: 10, width: 10, resizeMode: "crop-and-scale"}]) gives you width 10 if pan is supported and width different from 10 if pan is not supported, so you get the exact same fingerprinting as in the basic set (note: naked values in advanced are all exact).


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Received on Thursday, 24 September 2020 18:21:29 UTC