4 weeks ago I found an injured pidgeon, took it a rescue place and got chatting to the owner about chickens. I came home, searched for chicked coops on my business laptop. This laptop runs Firefox, uBlock and Ghostery.
Last night, my wife has Facebook adverts for chicken coops pop up on her laptop. We've not spoken about chicken coops since, I've not searched for chicken coops since the original search, she's not searched for chicken coops on her laptop and she's not used my work laptop.
Creepy.
If they want to track you with a "normal" browser, they'll find a way of doing it.
Your fingerprint and her fingerprint are stored as highly related by advertisers. Because you shared so many things in the past. IP, Location etc.
This is exactly what browsing via tor is trying to make harder. To fingerprint you.
You are right that fingerprinting can not be avoided completely. See the recent thread about FB tracking your mousemoves. Advertisers can use anything you do as a fingerprinting signal. It's not possible to use the web without interacting with it.
But your experience is not an example of why using the tor browser would not work. It's an example of why it is developed in the first place. To make fingerprinting harder.
It might not have happened through the work laptop. Did you give the bird rescue your contact info, or even just call them before showing up? If their phone has the facebook app on it, then facebook knows you were in touch with them the other day. They already know your phone number, because by now several of your friends and relatives (if not you or your wife) have given facebook permission to import all their contacts.
The rescue place is really just a private house and a old woman who loves animals... she doesn't take contact info and I'm not sure she has a Facebook account or any social presence.
Doesn't Ghostery allow in certain trackers if they're paid? I remember there was some controversy about their funding model.
I use uBlock Origin + uMatrix currently.
Your tracking situation doesn't seem out of the realm of possibility though.
1. You searched for Chicken Coops at a place.
2. That same laptop connects to your home Wi-Fi.
3. The user (you) who searched for chicken coups is connecting from a new IP.
4. Some ad engine rule says that IP belongs to a household (this probably doesn't matter; makes me wonder if people in a Starbucks get ads intended profiled against other customers).
5. Now let's just advertise chicken coupes to everyone in that house.
So in theory, this tracking attempt can be done with just a cookie and selling sets of IP+search word data, right?
> Doesn't Ghostery allow in certain trackers if they're paid? I remember there was some controversy about their funding model.
The controversial thing was that you could opt-in to sending Ghostery data about what things it blocked, and Ghostery would then sell statistics about what things got blocked most often so publishers could update their website to replace the blocked items.
> makes me wonder if people in a Starbucks get ads intended profiled against other customers)
unlikey, at your home location, usually it is just the same few people all the time.
At a coffee shop there might a couple of the same people every time, but also lots of other random people. So would be easy to ID home location / office location / public space location.
Or perhaps they know the location is a coffee shop from their facebook location ID.
Two ways I'm aware of. If your time at the coffee shop is regular (arrive at 3:15 because that's when your break is from work) they can place you with other regulars (you go there with your wife every day after work, you get dark roast and she gets a tea). Second if you're a black hole of privacy features and everyone else around you is not... well you get identified that way. Like herd immunity there is a risk if your behavior makes you an outlier.
Imagine for a moment though that they can't serve you ads directly. I wonder if anyone has done research into saturating adds in a coffee shop for all the patrons? Everyone sees the same add for the Dallas Cowboys and triggers a conversation about football. Now you didn't see the add but everyone around you is talking about football.
Last night, my wife has Facebook adverts for chicken coops pop up on her laptop. We've not spoken about chicken coops since, I've not searched for chicken coops since the original search, she's not searched for chicken coops on her laptop and she's not used my work laptop.
Creepy.
If they want to track you with a "normal" browser, they'll find a way of doing it.