WebGL hash consistency across different machines using the same profile/seed

[nvqktcq]

Hi, I have a question regarding fingerprint portability across machines.

If I use the same profile and the same seed on two different machines, will the WebGL fingerprint/hash remain identical between them?

More specifically:

• Does InvisiblePlaywright fully virtualize/spoof WebGL renderer/vendor and related rendering outputs?
• Or can hardware/driver differences between machines still leak into the WebGL fingerprint?

For example:

• Machine A: Windows + NVIDIA
• Machine B: Linux VPS / AMD

Would the WebGL hash still stay consistent across both machines with the same profile?

I tested this myself and noticed that the WebGL hash was different between the two machines even when using the same profile/seed, so I want to confirm whether this is expected behavior or if I might be missing something.

Thanks.

[feder-cr]

strings (vendor, renderer, extensions, getParameter values) come from zoom.stealth.webgl.* prefs derived from the seed, those match across machines.

gl.readPixels output doesn't. our WebGL noise is just +/-1 on ~12% of pixels on top of whatever the host GPU rendered. Intel vs NVIDIA vs AMD vs Mesa render differently at the base, so resulting hash differs too. no WebGL equivalent of canvas substitute_pixels currently.

quick check on the same machine: flipping substitute_pixels both ways, WebGL hash stays at 9048ab4c. so that pref only touches Canvas2D.

if you need a WebGL substitute mode i can take a look at adding one, just say.

[nvqktcq]

A WebGL substitute mode would actually be very useful for my use case.

I'm specifically trying to keep fingerprints stable when moving the same profile across different machines/GPUs, and currently the gl.readPixels hash changing is the main inconsistency I'm seeing.

Thanks for the detailed explanation by the way, that clarified a lot.

[feder-cr]

following up after testing this on windows specifically. my earlier answer was wrong for the windows case.

on windows the renderer/vendor strings are not seed-derived. they're deliberately left empty so the build reports the real GPU. the reason: the getParameter() values (max texture size, viewport dims, etc) come straight from the real ANGLE/D3D11 backend, and spoofing the renderer string to a different GPU while those stay real-hardware creates a string-vs-parameters mismatch that is itself a strong bot signal. reporting the real GPU keeps everything internally consistent, which is what matters for detection.

only the linux builds spoof to a fixed windows ANGLE identity (renderer and parameters together).

so to answer directly: same seed on windows+nvidia vs linux+amd will not produce the same webgl hash, and that's intentional. on windows each machine reports its own real GPU; the seed only drives the readpixels dither, not the GPU identity. a portable webgl identity across machines isn't something the windows build does today.