Drag to resize the width of editors in merge view

How do we implement any kind of dragging functionality to resize the widths of editors of merge view?

The type of resizing that would reduce width of one editor in exchange of expanding the other.

We are open to any kind of solution. For example, CSS styling, Dom manipulation and Event listener or combination of these

The styling of the elements that wrap the editor can be freely adjusted. Thus any kind of drag handle that resizes these on drag should work as normal.