I have been playing my own Minecraft Bedrock Dedicated Server since 1.20 release and just noticed that when opening the character inventory screen with "E" on the keyboard in Windows Minecraft Bedrock, each time it is as if the mouse is hovering/selected over the Helmet item regardless of where the pointer is placed (even in an open area not above the UI).

I've noticed that my helmets have been disappearing or being dropped inadvertently. I figure that if the inventory of the character is full, this bug is causing the item to be dropped without the player realizing as the mouse is being clicked and item selected and thrown.

I don't know when this issue started to happen, but it's easy to reproduce. Simply just open the inventory screen by pressing E and notice the tooltip for the helmet show up. If you immediately click after opening the inventory screen, the helm is picked up. If you end up clicking the helm and exiting out when your inventory is full, the helm is dropped.

Here is a video to demonstrate.

https://1drv.ms/u/s!ArY94VX-LZYIkGHrQCv9EctgqH-g?e=GjFQPd

I think just by fixing the auto hover of the helm during opening of inventory would fix this problem so that players are not tossing their helmets or selecting them during a fast clicking motion, during mob fights, block selection etc.