There is no way to cancel moving a feature card once you start. You may not remember where it came from, or where it came from may not even be in view any more. Naturally I want to drop it somewhere that doesn't make sense or hit the escape key.
It would be nice to be able to undo during or after moving a card.
Thank you for the idea. Given the low volume of support for this idea, we do not have plans to make updates in this area at this time. We hope you can understand.