Recently I often have to merge changes to the older environment, unfortunately, because this process is exhausting. The target environment is way behind (which is basically the reason why we need to use merge), and so the merge dialog pre-selects everything in the source module (as the newer version), and I have to spend a lot of time simply unchecking all that, because usually I need to merge only few elements. A module can be big and there can be conflicts, which turns this into nightmare. The quickest way I know is to go down with arrow key and use space to select, but every time when it hits the conflict - the popup dialog requires mouse click. To make things worse, sometimes studio does automatic merge, and it's not always possible to unselect it. Then after spending around 20 minutes on this, I find that the action was incorrectly merged, and this means starting again.

Anyway, this could be significantly easier if there was an option to select everything from either source or target, and then you would go and modify only the elements actually needed.