Like the 5th picture down you can see him standing (he uses a standing desk!) and if you blow up the screen, you can see part of an emacs window on the left hand side. I believe he also was using emacs shell windows as well, but not 100% sure.
Direct Link: https://d2r55xnwy6nx47.cloudfront.net/uploads/2020/04/DK_VC_...
I can't emphasize enough how incredibly nice and welcoming he is. He is bursting with enthusiasm for computers, and my wife and his wife had to almost restrain him so he would sit for his pictures, because he would start talking to me again about computer related stuff.