I also have the multiple browsers open, constant dialogue and am a daydreamer (I refuse to call it maladaptive though, I enjoy my daydreams and use them as a refuge if I am feeling stressed or sad or to pass time when travelling or waiting).
I have no idea what people who don't daydream do during these times!
Although I have lots of different streams of thought, I can choose which one is dominant and say "not you" if I want to push one to the back and bring another to the foreground, leaving the others to continue running in the background.
I have wondered about ADHD in the past (largely because I am the most restless person I know - sitting the whole day in an office chair was absolute torture for me, and I have been known to turn down trips to the theatre for any play over two hours), but I am also capable of intense concentration on a single item for work.
I have an interest in lots of things so I quite enjoy sending one strand of thoughts off to consider something, for example, considering all the varying reports I have read on the merits of the Coronavirus tiers and distilling a view on them, is one thread I have running in the background at present.