> I think it may just be because in both cases it opens in a new tab with the view-source modifier, it treats it like you just opened a copy of the page in a new tab?

Interesting. I never payed attention to the resource prefix. Are those standardized at all? Both Firefox and Chrome use the same "view-source:" prefix.

> I believe if you open the inspector instead it does not issue a new request.

The inspector shows the current DOM, not the original loaded HTML, which could be different. It's probably "good enough" as in most cases the original HTML would be the simpler one (say a single div for a single page app) and the live DOM would show what look like right now.

It's not the prefix/scheme that's important, it's the fact that it's a new tab.