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I see there are similar questions from 2012, but cannot find something more recent.
The frequency of "Are you a human" checks has become excessive recently - I get them on the majority of searches I make. Most of the time I am not logged in, but my device and IP are not predictable.
I suspect that the cause is most of the time that I am making a search on a stack exchange site using the search function itself I am looking for a list of interesting looking discussions. So for instance, I will search for "bug compatibility" to see if there are any interesting looking tales of what folk have had to implement over the years.
I can see how this can look a lot like a bot. But surely I'm not the only person who uses stack exchange sites like this?