> I wouldn't particularly discourage the rumor.

You might as well just admit to encouraging disinformation campaigns against things you don't personally like.

Your friend's friend says the Facebook app tracks conversations. Do you

a) Vaguely agree that Facebook is awful, and removing the app is a good idea,

b) Start explaining how a detailed log of every app user's location, time spent reading each story, typing speed, searches, lists of other apps used (or in use), full lists of contacts, calendar events, text messages, phone call history, photographs, nearby WiFi networks and battery statistics can be combined with website-based Facebook use and tracking cookies on other sites, allowing Facebook to create a detailed profile of each user, and that's why they showed the creepily-relevant advert.

I would usually choose (a), unless the discussion is specifically about data privacy. (b) is not literally listening, but it's close enough for a casual discussion.

Er, I wouldn't choose either. If a friend asked me if Facebook tracks conversations, I'd just give it to them straight from the horse's mouth:

https://newsroom.fb.com/news/h/facebook-does-not-use-your-ph...

It's not really disinformation, just a slight inaccuracy. For years they were collecting text messages and call logs:

https://arstechnica.com/information-technology/2018/03/faceb...

Not quite "listening to calls," but not too different either. It shows you where their heart is.

The claim was not that they were listening to calls (which they also directly claim they don't do, according to your article), it was that Facebook listens to you through the app. They've also explicitly stated they don't do that, as well.