What I expected to happen was:
When picking up an item from a slot where the item is already over the stack size limit, the maximum amount that can be picked up should be moved to the cursor, the rest should remain in the previous slot.

What actually happened was:
When picking up an item from a slot where the item is already over the stack size limit, the entire stack is picked up.

Steps to reproduce:

1. Join either a 1.20.2 or 1.20.3-rc1 world with operator permissions
2. Type: 

   /give @s minecraft:chest{BlockEntityTag:{Items:[{id:"minecraft:dirt",Count:127b}]}}

3. Place down the chest and open it
4. There are 127 dirt items in slot one, this is displayed incorrectly as 64 due to another bug MC-267171
5. Pick up the dirt in slot one.
6. The stack size limit is not applied to the items when they are moved to the cursor.