I could not see the "Retrieve Message" button at the bottom of the page - my focus was on the upper portion of the screen, wondering why there was no "undo" button anywhere in the command line up top ...
but I see it now - old dog learns new trick ... ha ha ha
maybe that button should look more prominent when active - the grey parts of the active page seem to blend together, and the Retrieve button should be next to the Remove All button so that you immediately see an option for undoing a delete
