See students' drafts in the graders interface

[Evgeny Kotelnikov]

It might be convenient for graders to see submission drafts. Example: students often upload files, but forget to submit them, and therefore miss the deadline (how to make it happen less often is a separate question). The grader might want to check the time when the files were actually uploaded before making a decision to extend the deadline. Currently, the only way to do it is to login under the student and look at the draft.