Wouldn't this make it obvious that the user is browsing in private mode? While I get that might be preferable to leaking information, its also not an ideal solution either.
I'm very interested in this thread. Other replies here are correct - there are many ways that sites try to detect private browsing, and many ways they can get it right or wrong.
How do people feel about the "stealth" design goal of private browsing? Should it be a goal? What about a hide-in-a-big-crowd tactic? (E.g., how Tor tries to make all its users look identical.)
I think this shouldn't just be a goal for private browsing, this should be a goal for browsing period.
Shouldn't the default be to just send the top level domain (if anything) of the source site as soon as you go somewhere else? The next site can't possibly use the complete url of the referring site for any (non-shady) purpose?
1. What does it matter if the creators of a website are aware that a user is using private browsing to view the site? In other words, what would they do with this information?
2. As it's possible to strip out referral information using other means, assuming there's a practical use for this "private browser user" information, what could the site creators do to guard against false positives?