Shift-clicking on trade screen broken

Steps to reproduce:

1) Find a villager to trade,

2) Put whole stack of items into trade slot.

3) Shift-click on the emerald icon on the right.

4) Result:

• The trade will be locked;
• You'll get one emerald;
• You'll get some experience;
• Actually nothing will dissapear from your inventory (nothing will be sold to the villager);
• After exiting trade screen and entering it once again the experience bar of the villager will be reduced;

 

Edit: buing one item per click (without Shift key) seems to work fine.