Still relaxed, head sagging mid-futon (2,3)
I believe the answer is:
as yet
'still' is the definition.
(I've seen this in another clue)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for as yet that I've seen before include "Up to this point in time" , "Thus far" , "Up till now" .)