Hello all,

most of my work now involves using quite large wide monitors and having
the editing of src blocks open windows below is less convenient than
splitting horizontally.  I have added the option to split
horizontally.  See attached patch.

However, ideally, I would like the option to specify a function as
context matters: sometimes a vertical split is better, sometimes
not.  But implementing this was beyond my emacs-fu.

Thanks,
eric

-- 
Eric S Fraga via Emacs 27.0.50, Org release_9.2.4-379-g1b74ae