GUI Background doesn't darken for certain GUIs

When opening a crafting table or enchantment table, the background part of the GUI (which still shows the surrounding area) darkens. However, in the latest 1.12 snapshot, other GUI's lose this function, such as chests, hoppers, and furnaces. It also doesn't matter whether an item is in the GUI or not, and whether the actual item is in use (furnace is cooking, brewing stand is brewing, etc.).

In the screenshots, the left items are the ones affected by the bug.