If you shift+left click when in the saved hotbars section of the creative crafting menu, the item you shift-clicked from your hotbar will just disappear. Platform: Windows 11, Minecraft official launcher, downloaded from the Minecraft Java + Bedrock Bundle from the Microsoft Store.

Steps to reproduce:
1. Must be playing in 1.19.3 (or a version with the saved hotbars menu, it seems to me)
2. Open the creative crafting interface by pressing E in a creative world
3. Go to the saved hotbars section
4. Shift-click any item in your hotbar

Expected result: Item should not be able to be shift-clicked and will remain in your hotbar, as there is nowhere to shift-click it to

Observed result: Item disappears from your hotbar, and can't be found anywhere in the survival inventory section.

https://imgur.com/a/n8gmLbI