When a question is put on hold as unclear (for example), is there a way to propose that it is reopened? Like flagging, but flagging for good and not for evil :) (just a joke, please don't get it the wrong way, if flagging was a sin I would be guilty of it). In particular, I think this question

Do Gaussian process (regression) have the universal approximation property?

is clear enough to be answered and I would like to post an answer.