To add it, just go to the corresponding actor and add the InventoryExtendManager component to the actor of your choice.

Then you can access all the features of the components.

Note that in Experience by default, this component is added to all controllers.

But you should add it to actors that don’t have a controller, like chests.

 

Example:

 

Now, set Inventory Size and adding a Item in inventory. 

 

Or simple use adding and expand Size. (unlimited)