Mates unhappy with Jeremy? They decrease (5,5)

I believe the answer is:

steam irons

'they decrease' is the definition.
(irons remove creases from clothing)

'mates unhappy with jeremy?' is the wordplay.
'unhappy' indicates anagramming the letters.
'with' says to put letters next to each other.
'jeremy?' becomes 'Irons' (actor Jeremy Irons).
'mates' is an anagram of 'steam'.
'steam'+'irons'='STEAM IRONS'

I've seen this clue in The Guardian.

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