[muzani]

I do most searches in an incognito window so it can't be browser history.

In some cases, it's even something like my wife joking about selling the car to a friend on WhatsApp, and suddenly Facebook show ads where you can sell the car. One time I told my wife to buy something at the grocery store (verbally, no text) and FB shows me the ad for that exact item.

[vbsteven]

> I do most searches in an incognito window so it can't be browser history.

Incognito mode is mostly a convenience for you to do browsing without saving local history or cookies. It doesn't stop tracking.

I assume the fingerprint is different in incognito versus a regular window. But unless you are using VPN/adblockers/pihole/etc your browser is still executing third party JS and potentially sending tracking data to google using a plain https connection coming from your residential IP.

I can imagine it's not that hard for Google to link different requests from the same IP with slightly different fingerprint data to be coming from the same user.

edit: and for searches it is even easier, because you are communicating directly with google by performing the search, no tracker or JS necessary.

[xtracto]

We had a similar thing happening to us: Wife and I have no kids and have no plans to have them. Kid related stuff is just not part of our everyday interactions. One day we visit some friend who are a couple with kids and in that visit we TALK about babies and rising kids and whatnot. Next day my wife (who has the FB app Installed), starts getting kid's diapers ads. I dont have FB app and I dont get those ads.

She uninstalled the app after that.

[vsl]

Anecdotes like this are plausibly explained as https://en.m.wikipedia.org/wiki/Frequency_illusion