[owenfar]

It was tested and should work on all browsers (though the extension is only chromium based at the moment).

But for the sake of simplicity, we placed that badge since it's the most familiar icon to the wider audience. Initially most of our visitors thought it's an OS they have to download, this helped solve some of the doubts.

I had to create Facebook just for this, because whether we like it or not, it's a huge platform that shouldn't be missed.