Since: nightly builds only
Returns the text from the specified region.
end_xare the starting and ending cell column, where 0 is the left-most cell
end_yare the starting and ending row, expressed as a stable row index. Use pane:get_dimensions() to retrieve the currently valid stable index values for the top of scrollback and top of viewport.
The text within the region is unwrapped to its logical line representation, rather than the wrapped-to-physical-display-width.