When a developer pushes a large commit, or a story has several commits which has lots of files to review, it's very to review it in any code review tool. The best way should be in the IDE, which enables you to easily jump from one method call to its implementation which is another class. etc
How do you tackle this problem?
I simply leave the review open in my web browser, then drill around, test, (even sometimes spike refactoring suggestions) etc in my IDE, and each time I find something I want to comment on, just CMD-TAB back to the code review and leave a comment.
I spend a lot more time reading and playing with the code for a code review, than leaving a comment, so this setup works well for me.