Sometimes patch authors can submit many diffs of their changes. As a reviewer, it can sometimes be difficult to figure out which diff was the one that we previously reviewed, and so it's hard to select the proper interdiff. Currently we need to read the change history, find our review, then search upwards to find which diff it was for.

It would be great if the history tab had a reviews column which contained an icon (either check mark or X) for any associated reviews for that diff. This gets a little bit more complicated if there were multiple reviews from different people on the same diff. A nice way of handling this might be to display multiple icons with the author name being displayed in a tooltip.