[ESS] how to change default emacs behavior, upon running R code, from 2 side-by-by side frames to top-and-bottom frames?

[Jeremie Juste]

Hello,

> When I execute a line of R code, the R buffer opens up as expected, but
> it opens in a frame adjacent to the frame containing my source buffer. I
> would like it to open the R buffer as a frame below my source code,
> rather than adjacent to it.Â

This section of the documentation might address your issue. You can
execute the command below for quick access.

(info "(ess) Controlling buffer display")

HTH,
Jeremie