Milkevs Essentials

this allows items you pick up to be inserted *into existing stacks* in your toolbelt. The pickup priority is: Filling up hotbar stacks, Filling up toolbelt stacks, Filling up hotbar empty slots, Normal Priority. the toolbelt will not insert items into empty slots. This is particularily useful if you, for instance use one 'hotbar' for tools, and the other 'hotbar' for building blocks like I do, then when you missplace a block, and switch over to your 'tools hotbar' side to break it, it will be picked back up into the 'building hotbar' assuming it wasnt the last block from the stack.
This new functionality comes with a modified pickup sound to differentiate from items going into your inventory, and has its own config option if you wish to disable it.