Put back missing slot hiding code

src/Classes/ItemsTab.lua

@@ -132,6 +132,10 @@ local ItemsTabClass = newClass("ItemsTab", "UndoHandler", "ControlHost", "Contro
 				end
 				swapSlot.abyssalSocketList[i] = abyssal
 			end
+		elseif slotName == "Ring 3" then
+			slot.shown = function()
+				return self.build.calcsTab.mainEnv.modDB:Flag(nil, "AdditionalRingSlot")
+			end
 		end
 		if slotName == "Weapon 1" or slotName == "Weapon 2" or slotName == "Helmet" or slotName == "Gloves" or slotName == "Body Armour" or slotName == "Boots" or slotName == "Belt" then
 			-- Add Abyssal Socket slots