This may likely already be a planned feature that is in the works but I wanted to post an issue to gain some visibility on when this may be implemented.

We need to the ability to have a region to consume the vertical space of two or more regions like the following:

-------------A   D
-------------B   |
-------------C   |

D -------------A
| -------------B
| -------------C

The above examples require only one level of "grouping" which will suffice for our needs but the examples portrayed in #1682904: Known limitations of this layout builder perhaps portray multiple layers of grouping.

If the layouts above are already supported, please point out how this may be achieved. Otherwise, this ability seems critical for our use of this module and perhaps for others as well.