Relaxing OAP is ponderer thinking of nothing in particular (1,6,2,4)

I believe the answer is:

a propos de rien

'thinking of nothing in particular' is the definition.
(French phrase meaning 'apropos of nothing')

'relaxing oap is ponderer' is the wordplay.
'relaxing' is an anagram indicator.
'oap'+'is'+'ponderer'='oapisponderer'
'oapisponderer' anagrammed gives 'A PROPOS DE RIEN'.

(Another definition for a propos de rien that I've seen is " As an aside".)

I've seen this clue in The Times.

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