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Thanks, this was super helpful! But I had to make a change to the second cell to get it to work correctly:


{ "keys": ["alt+shift+7"],
   "caption": "2 cols (full - 2)",
   "command": "set_layout",
   "args": { "cols": [0.0, 0.5, 1.0],
	     "rows": [0.0, 0.5, 1.0],
	     "cells": [ [0, 0, 1, 2], [1, 0, 2, 1], [1, 1, 2, 2] ]
	}
},