How can you delete the submission comments in the inbox of canvas?
Scott, greetings! You can't delete submission comments out of the Inbox because they are tied directly the the actual submission comments on the assignment. If you wanted to delete them you would have to delete them from Speedgrader or the Gradebook - which would then also prevent the students from seeing it, so probably isn't recommended.
Scott, also please be aware that students who have their notifications preference for Submission Comments set to "Right Away" will already have received a notification of the comment; deleting it won't change that.
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