This is NOT a solution to the question.
Being able to see the gradebook history is a start... but this is not a way to undo or revert a change.
I accidentally overwrote all the scores for one assignment when I was assigning a default score. Somehow the "overwrite" box got checked.
I found this post looking for a real solution. Seeing the gradebook gives me a way to manually change the 100 affected grades, if I'm willing to put in the work, since I can see the original grade. But the gradebook history doesn't even sort the students. Gradebook history gives me the data on 100 students' grades for this one assignment, but the students are all listed in a some random order. So I have to hunt for one student at a time and type in the new (old) grade.
Canvas has made it so easy to make a mistake, and virtually impossible to correct it.
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