Wrong nebuliser? Possibly do for granny? (4,5)

I believe the answer is:

blue rinse

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'do for granny?' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'wrong nebuliser?' is the wordplay.
'wrong' indicates an anagram.
'nebuliser' with letters rearranged gives 'BLUE-RINSE'.

'possibly' acts as a link.

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I've seen this clue in The Guardian.

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