To make the review process a bit easier to follow, there are a couple of features that are useful when dealing with a lot of commits and changed files.
The Changes from drop-down menu is helpful if you want to see the changes introduced by a single commit or a range of commits:
Next to it, the Jump to dropdown provides a list of all changed files that you can choose and jump to:
This might seem redundant when there's only two files, but it's powerful if there's a dozen of them as you don't have to manually scroll down the ...