See visual diff in review app
Often when I am looking at an MR that changes text / structure in the handbook, I constantly switch between the code diff view, and then the review app showing how the change looks in context of the web page itself.
I want to review the text changes. But I also want to see how the structure has changed. Seeing changes in structure (like indentation, paragraphs, lists, is very difficult in the code diff because it is markdown. Seeing the change in the Web IDE (i.e. &167 (closed)), could also be helpful too. But seeing it actually in the review app could be even more powerful because I see the end result right away in context.
In this example, you can see that I've removed a paragraph, and added another one. Rather than just seeing it in a code diff, I also see it in the review app.