Allow copy and pasting of a X by Y subset of a table like excel

For example:

Allow the ability to select the 2x2 square in the centre containing only Z's.

Right now, if you drag using your mouse, Confluence gives the impression that it is only selecting these 4 cells. On releasing of the mouse button, you get a resulting selection that encompasses:

Fix this, to allow copying pasting of subsets as well as 1xN subsets (which is effectively a column)