Items in Creative inventory can be duplicated by spamming hotbar hotkeys

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Hi! I cannot reproduce this in 1.16.3. Is this still an issue for you?

Yes... kinda
when trying to replicate the item wasnt duplicated but removed. Even after reloading the world the item was still missing.
You can replicate the bug by getting the game to lag (I started another programm).

I can confirm, just had to mash the number row while highlighting one of the upper slots in the inventory. Took some time, couldn't get it to happen outside of creative mode

Relates closely to MC-270503 and may be the same core issue. Can you still reproduce the bug in the latest version, 1.20.5 Release Candidate 2?

I wasn't able to reproduce this in the latest version.

I can still reproduce this in 1.21. The easiest method to reproduce this, seems to be by spamming the hotbar key on a second item in the inventory as well.