Happy with what's included (7)
I believe the answer is:
content
I believe this clue is a double definition.
'happy' is the first definition.
(associated in meaning)
'what's included' is the second definition.
(I've seen this before)
'with' acts as a link.
(Other definitions for content that I've seen before include "state of peaceful happiness" , "Elements" , "Quietly happy" , "Gist" , "Satisfied; volume" .)