Dupe Glitch with Shulker (works in 1.19.40)

So I have found out about a dupe glitch working in 1.19.40 and probably also above:

(did not find any open bugs so)

If you do the following steps

1. Get a Shulker Box and an Item to duplicate, further a Nether Portal
2. Place the Shulker next to the portal and Save & Quit
3. Get Back into the World and put the Item in the Shulker (asap)
4. Get into the Nether Portal, after getting into the Nether, Exit the Game through alt+F4
5. Get Back into the World

the Items should be duped.

Disclaimer: Yes, I am aware of the Bug where you Place the Shulker itself after Saving and Quitting. The Glitch performed above works the same but still in 1.19.40

PS: Also works with Stacks of Items or even multiple Stacks at once

Edit: Also works with shulkers (even multiple) by putting them in a chest{}