Appsflyer, meta privacy concerns

Per exodus-privacy:

To my surprise, my Avast Secure Browser is using appsflyer per the exodus online report, which can be used to assign identification to a device, track what is being browsed, etc. What exact information is it sending from the Browser that is supposed to be secure and private? Does it have an ID associated with it that ties directly to my device?

Also, why is Meta showing for Avast? Does it invade people’s privacy and send data to them? I pay for my subscription, I do not want to feed Meta.