Hotkey for deselecting chat text box?

[iRFNA]

There's the hotkey for selecting it (enter), which also submits what you've typed. But what if you type a bit and want to deselect the chat text box without submitting it yet? I've noticed clicking a random window will do so, but I haven't seen any key for it. Is there any, or a hotkey that does something else but also has the side effect of deselecting the chat box?