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In the revision history of edited posts, there is a helpful display that highlights the changes between the edited and the original. Often, while editing, I find myself looking back at the original question in another tab to make sure I've covered everything and haven't accidentally deleted anything (moving the mouse a few pixels too far while selecting lines to change, that sort of thing). It would be much more convenient, and I would be less prone to "oops, I missed a spot, too bad I can't edit my edit without submitting another edit" if I could see the same display from the revision history showing both the original question and what changes have been made while editing.

marked as duplicate by Charles, Hugo Dozois, Robert Harvey Dec 10 '13 at 20:26

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