1. Buy medication I never have bought or even searched for before at local pharmacy w/ credit card
2. Go to car, decide to test #Librem5 cellular by visiting my account on mobile.twitter.com
3. Immediately see ad for type of medication I bought!
No location tracking possible on this Librem 5 (used browser, not native twitter app), so either a crazy coincidence, or near-real-time reporting between CVS and #adtech w/ linking between my name, card, and twitter account.