Put the summary of the bug you're having here

What I expected to happen was...:
Block should have placed normally

What actually happened was...:
(Probably have to try yourself as I'm not good at explaining things)
METHOD 1: Block disappeared when attempted to place.
METHOD 2: Block changed to switched block

Steps to Reproduce:
METHOD 1:
1. Open Inventory and have items in hot bar
2: Hover cursor over item and use keys 1-9 to move item from 1 slot to another (move it to an empty space). i.e Move item from one slot to another using the number keys. Not key pad
3: Exit inventory and hold item in hand
4: Place block

METHOD 2:
1: Have at least 2 items in inventory hot bar
2: Use numbers 1-9 to switch item 1 (e.g stone), with item 2 (e.g sandstone). Say stone was in slot 1 and sandstone was in slot 2, now stone is in slot 2 and sandstone is in slot 1.
3: Exit inventory and place switched block (sandstone) on ground. i.e Sandstone was in slot to so switch it with stone in slot 1 using the number keys, then exit inventory and have the sandstone in slot 1 in hand and attempt to place it on ground.