Pay attention to what's in the editorial? (4)
I believe the answer is:
'pay attention to' is the definition.
(eg to heed a warning is to pay attention to it)
'in the editorial?' is the wordplay.
'in' indicates the answer is hidden within the clue.
'HEED' can be found hidden inside 'the editorial'.
'what's' acts as a link.
(Other definitions for heed that I've seen before include "Care, attention (paid)" , "Attend to, mind" , "Obey" , "Take to heart" , "Observe" .)