Merging stacks of items

[Bvz]

It would be great to have an option where you can merge all sets of stackable items into one stack. Unless I'm missing it, it seems that if you have two stacks of identical dyes (for example), even if you sort them the stacks are kept separate and you manually need to merge them.

Ideally keep it as a separate button/option, to not inconvenience people who like splitting stacks intentionally. Obviously this should still be subject to stack size limits.