Sometime last year I was taking a short bus ride home from a local supermarket in Leytonstone (London) when a passenger boarded with a slightly louder American voice. I thought he looked familiar then it hit me - Richard Stallman. I didn't have much time to decide what to do as he was about to get off at the next stop so I left the bus at the same stop and caught up with him. After an introduction and short conversat…
Does this make me a hacker? Donald Knuth was giving a presentation to celebrate someones birthday by debugging his old FORTRAN code. He was having trouble giving it since his PDF of his presentation was autoforwarding using Adobe Acrobat. I figured out that Preview would avoid this outcome. I think this is the largest contribution I will have to Computer Science.
I've seen Knuth give other (more recent) talks out of slides like that one (https://cs.stanford.edu/~knuth/karp80.pdf) where each PDF page is a possibly different size and he wants it displayed full screen individually, but don't recall that problem from other times… so the impact of your contribution may extend beyond that one talk!