[mianas]

This seems like the perfect thing to implement as a browser addon. If you think you need it, install it. Otherwise, the code doesn't touch your install.

Much like the container tabs extension, in terms of requiring an addon for certain functionality. Or, if mozilla doesn't do it themselves, a (horrifying though warning) third-party-extension with an external helper application to connect to the serial device, and a API polyfill injected into every page.