is there an equivalent of shift clicking to view many file changes in a pull request?

Hmm can you expand on what you mean here? Is this in the UI?

Yeah in the GitHub web app, when you are reviewing a pull request you can hold shift and click on the “viewed” button

I'd like this as well! Might be a Refined GitHub feature, though–I'm not sure it's natively available on the GitHub UI.

ah good point, I sometimes forget I have that installed haha