There are a few john doe scripts kicking around now, as there have been a few variations of the HIT. That being said, I'd do a search here on MTC for the word script or doe, with the member
@SarahAshlee90 as I believe she has created and posted a couple of those scripts here on the forum. Alternatively, you could search greasyfork for john doe. Might have to trial and error to figure out which script is which, but essentially, when you get the right one, it should select a bubble for each answer by default, not just the first question. I believe they can be configured to submit upon hitting the enter key as well. When I have more time, I'll link them.