"Without you" guitar tuning?

[xhector]

Hi!

Does anyone have any idea of which guitar tuning does Lindsey use for Without you? (old demo or new live version sound similar)
The sound is very folksy, with some really high notes (some strings an octave above?) - it sounds like a 12-string but it seems a normal 6-string in the concert videos. And it just sounds to me like like the tuning is not the standard.
Anyone can help?

Thank youuu!