Firefox sends your uptime

[.FUF]

> 1. Re: other browsers: Is Opera better in this regard?
In this regard, yes. But, of course, I'm not saying "opera is better" ;)
Opera simply doesn't send your uptime in TLS Client Hello packet (as
well as IE).

> 2. Would it be possible for Privoxy to be patched to
> filter this out, or is this information already SSL
> encrypted when it is sent (excuse my ignorance)?

No, it's not encrypted (you can check this in your favorite network
sniffer), so it can be fixed by Privoxy or similar app.