A new Firefox extension called awawausb adds WebUSB functionality to the browser through native messaging. The extension requires both installation in Firefox and a separate native stub program on the user's computer. Users can install signed versions via .xpi files or load temporary add-ons for testing.

Prebuilt binaries are available for macOS, Linux, and Windows across multiple architectures including ARM64 support. The native stub uses Rust and requires specific system configurations - macOS 10.15+, Windows 10+, and Linux kernel 4.8+ with udev support. The project includes cross-compilation support and detailed setup instructions for various platforms.

This extension fills a significant gap in Firefox's capabilities, as WebUSB support has been limited compared to Chrome. The architecture uses a JSON manifest file placed in platform-specific locations to enable communication between the browser extension and the native stub. With comprehensive documentation and prebuilt binaries, developers can now access USB devices directly from web applications in Firefox, opening new possibilities for web-based hardware interaction.