There isn't one I'm aware of I'm afraid... it may be it's an extension that would need adding to codemirror in the IDE
That's too bad... Thanks @Gordon for your quick answer.
@Gordon started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
There isn't one I'm aware of I'm afraid... it may be it's an extension that would need adding to codemirror in the IDE