The Feeble, Robust, and Powerful offering item stacks use a ~6 second timer when holding a button to delete, as if the entire stack will be deleted (in line with other stacked items which delete the whole stack), but only a single item in the stack gets deleted once this completes. This seems unintended; either the short (~0.5s) delete time should be used and delete a single item, or the long delete time + full stack deletion. This is particularly painful for clearing out a full stack of 99.