Firefox 151 for Desktop now supports the Web Serial API, enabling web applications to communicate directly with serial-connected hardware like microcontrollers, development boards, 3D printers, and USB power meters without native software. The implementation was tested with Adafruit's CircuitPython workflows and supports devices like ESP32 boards, Raspberry Pi Picos, and LEGO devices. Security is handled via explicit user permission prompts using add-on gating, with no device enumeration or fingerprinting exposure. Mozilla is also pursuing standardization of the Web Serial API through WHATWG. Enterprise deployments have Web Serial disabled by default with policy controls available.
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Support for Web Serial in Firefox 151 for DesktopWhat is Web Serial?Security and PrivacyStandardizationFeedbackAbout Haik AftandilianAbout Greg Stoll388 Impressions