Unique id for each Firefox & Chrome extension installation

Question

Is there a way to generate something like a "computer id" that will be different on each computer on from a firefor and chrome extension to use for tracking purposes?

I mean, I want each extension installation to have a unique id that will be always the same on that computer, but different on each computer.

The id doesn't need to be the same on both chrome and firefox extension

Answer 1

I end up just generating a random guid with js and storing it as a normal preference the first time the extension runs.