[lmm]

I have very little knowledge of surveillance but I used to work in the ad industry. There are a lot of signals, all of them noisy in isolation, but taken together they paint a very clear picture of who you are. Even a "normal" browsing history is probably enough to identify most of your demographic characteristics - age, sex, sexuality, .... I'm not sure what exactly you might want to hide, but it's hard to imagine it wouldn't show up.