Origin of Pluto

Also sent in by Jovan. Busy man. At https://astronomynow.com/2018/05/26/evidence-found-for-giant-comet-theor… … what is the origin of Pluto? Is it a planet – or something else. It is being suggested Pluto is a great comet – of sorts. They say it is an agglomeration of a billion comets (in other words an inestimable number of comets). Another idea is that Pluto formed from coldices with a chemical composition similar to the Sun (but the giant comet theory is gaining traction it is alleged).