[ComputerGuru]

So fwiw, browsing history shouldn’t be anywhere near that big making it unlikely there what it was. It compresses well, if they were to do it I’m sure they’d do it at regular intervals instead of a years’ worth at a time, etc.

And, of course, Firefox is open source and this wouldn’t be kept a secret.

[windowliker]

In which case I'd love to know what it was doing sending that much data to Google IPs when I don't use Google services...

I've read all the Mozilla help pages about what automatic connections Firefox makes and it wasn't accounted for there (unless possibly something to do with SafeBrowsing.)