He reads about what paste does (7)

I believe the answer is:

adheres

'what paste does' is the definition.
(sticky paste adheres to things)

'he reads about' is the wordplay.
'about' indicates anagramming the letters.
'he'+'reads'='hereads'
'hereads' is an anagram of 'ADHERES'.

(Another definition for adheres that I've seen is " Sticks (like a stamp)".)

I've seen this clue in The Globe and Mail.

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