Sorry about this I have looked into it extensively and worked together with our accessibility team. Right now we need to have a certain degree of accessibility in the game or we are not allowed to do any more updates. One of the requirements is to be able to navigate in menus without using the mouse. Tab was implemented to have that functionality and it takes president in the inventory since there is a button in there that needs to be accessible. Trying to fix this issue has highlighted several issues with our system for assigning buttons to specific actions. If we fix the bug with tab not having to be bound to accessibility we have to make it possible to rebind the focus of buttons. Doing that will clash with showing players online on a server which is tab by default and to fix this we need to do more extensive work on our underlying system. Right now it is out of scope for us to fix this in 1.14 but is definitely something we want to fix further on why it is postponed.
Binding "Open/Close Inventory" to Tab only allows you to open your inventory. To close it you must push Esc. This does not happen with any other key.
For instance, if you bind this function to G, pushing G will both open and close your inventory.
is duplicated by
MC-145745'TAB' Key no longer viable for Open/Close Inventory
MC-145873Tab key does not work when bound to inventory
MC-145988Remapped open inventory key not working properly
MC-146084Open/Close Inventory key does not close inventory.
MC-146124Tab in survival inventory would not close it