Solid-fill canvas reads back perturbed (engine-level farbling, e.g. Brave)
br.canvas_noise · convicts
What it catches
Brave farbling adds per-session canvas noise; a solid fill read back exactly proves no farbling, any deviation proves it (reference-free). Privacy-tool tell = elevated risk; weight corroborates. v0.73.3: per-browser N/A — a privacy browser perturbs/blocks the canvas readback BY DESIGN (Brave Shields farble it via browser.is_brave; Tor/Mullvad/RFP-Firefox block it to uniform-white via browser.rfp_browser), so a session positively identified as one has this artifact dropped by the detector (detector.applicability) — a real privacy-browser user is not convicted; a Chrome-claiming farbler with NO such identity still convicts.
Signals it reads
browser.canvas_noise
How it fires
present
Evaders it caught 1
Bypassed by 10
Frontier evaders that reach the detector uncaught (scored only suspicious, defeating every convicting tell) — this check is not one that stops them. The red-team frontier this detection still has to convict.