That's certainly fishy but it doesn't rule out other methods that rely on statistics. For example, how many other people have visited that apartment and within

That's certainly fishy but it doesn't rule out other methods that rely on statistics. For example, how many other people have visited that apartment and within a few hours searched for window grills and latches? Perhaps all of them. Still, use Signal is the answer. The more people that use it, the more people will use it and the less we'll have to worry about whether messaging apps owned by ad companies are e2e.