I've had exactly the same experience today, having been asked to complete a captcha (of a type I haven't seen before—rotating a 3D object) after every prompt. I

I've had exactly the same experience today, having been asked to complete a captcha (of a type I haven't seen before—rotating a 3D object) after every prompt. I'm logged in and a paying subscriber of more than a year. I assume it is a bug.