AliExpress's silent WebAudio fingerprinting breaks Bluetooth multipoint on PC

A developer discovered that visiting AliExpress in Firefox or Chrome silently breaks Bluetooth multipoint audio on their PC, causing music from their phone to pause or stop while the page is open. The culprit isn't autoplaying video or ad media, but hidden WebAudio fingerprinting code embedded in Alibaba's security scripts, collina.js and fireyejs.js, which are hosted under the AWSC directory on assets.aliexpress-media.com.

The scripts create two AudioContext objects after the page sits idle for a few seconds, then build audio graphs consisting of a sawtooth oscillator, an AnalyserNode, a ScriptProcessorNode, and a GainNode set to zero, all connected to AudioContext.destination. Though the gain is zero so users hear nothing, the browser still actively processes the graph, which forces Windows or Firefox to keep the Bluetooth audio path alive and prevents multipoint headphones from switching cleanly back to the phone. Closing the tab or muting the tab doesn't help — only closing the page restores normal audio. The scripts also query canvas, WebGL, screen dimensions, hardware concurrency, plugins, and other browser properties, confirming this is a fingerprinting tactic designed to detect automation and bots, with the audio processing being a side effect that disrupts legitimate users' Bluetooth audio.