Could the separator between map and text pane become movable?

[lukeknipe]

I love geojson.io and use it a lot. But when using it to edit attribute data, I find that json/table/help section of the browser window is too small to use without a lot of horizontal scrolling. On occasion, this cumbersome mouse motion has caused my browser to navigate away from the page, causing me to lose whatever unsaved data I was working on.

Being able to adjust the relative sizes of the map and text pane would be a great help. Currently, you can close the text pane with the arrow button near the bottom, which effectively makes the page all-map. But you can't do the opposite, nor can you adjust it continuously (with a hand-grab or something like that). How hard would this be?