This is happening to me with insane regularity, although I usually notice it in Google searches rather than on Facebook. Recently I met a gentleman for the first time, who told me that he ran an planning / design industry webinar series called the "Performance Network". I'd never heard of this so he suggested I Google for it. I got as far as typing "perf" on my phone before that's what the autocomplete suggested. Freaked the hell out of both of us.

This kind of thing is now happening a few times per week. Are there any non-eavesdropping explanations for how this is possible?

If you could show it to others you'd become rich and famous.