It doesn't work on creative survival or adventure mode.
If i try and split a stack for example or something into half with control click on the item then it just doesn't work.

I expected it to make half a stack out of one stack.
I thought it should split it in two.

I just picked it up as if i would just normally move it in my inventory.
It didn't split in two.

Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
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