I generally don't care for "Confirm" dialogs... but... Due to a flaky mouse, while scrolling the folder list, my system got a 'move folder' event. The folder that got accidentally grabbed/moved has 273 sub-folders and nearly 28000 messages. Searched for hidden confirm/move options; but none found. This "move" brought to light that, accidental or deliberate, large moves take quite a while and there's no way to stop/abort the process. Even [fg+]Ctrl-Z is ignored until the move completes. Could a confirm dialog be added? Stopping a move is another option, though it probably would only be possible between folders... and only if cache and filter updates happen in sync with the moves.
Re Ctrl-Z... ignore that comment.
By default, CM *does* display a "Confirm Move" dialog. It also has a check box that allows you to disable it for future moves. Maybe you inadvertently disabled the confirm dialog some time in the past. Look for warn_dnd in CM's prefs file. Probably from 0 to 1. With CM *not* running, obviously.
Damn. That should read: ....warn_dnd. Change it, probably from 0 to 1......