Removing a book from offhand does not check for an available inventory slot from hotbar

[DrKusachki]

When trying to unequip a spellbook from a hotbar (i.e. if you have it bound to a hotbar slot and unequip it by pressing the corresponding number button) with a full inventory game doesn't state "You have no room left in your pack to unequip a [book]", it instead places it into a nonexistent inventory slot. Book after that is still available to use from the hotbar, but doesn't show up in inventory, showing itself only after sorting it.

This is on a current steam version of the game