The diff viewer only shows a limited number of changes to a file with a "..." being shown at the bottom. I often have to use an external diff tool due to this limitation. I would prefer to use the SourceTree diff as it allows for selective staging of lines and hunks which I can't do with an external diff.

As such it would be really good if there was a way to view a diff for the entire file rather than cutting off the end. Maybe allow clicking the "..." to load more of the file or something like that.