Hey Lewis, good question! Sharing files over dropbox is super useful, and something I do often. In this case, I think you’re able to do it because dropbox is in the same place on both computers. For example, mine is at C: -> Users -> Jonathan -> Dropbox on both of my computers, so since my username is the same, the path to it is exactly the same as well.
Also, good catch on the video! I think while recording I hovered over “absolute” and then moved my mouse up to “relative”. But I coughed or something while moving and cut out that noise in editing and didn’t realize it made it look like I was clicking something else. Apologies for any confusion!