Opened beer in shifting dunes (8)

I believe the answer is:

unsealed

'opened' is the definition.
(similar in meaning)

'beer in shifting dunes' is the wordplay.
'beer' becomes 'ale' (type of beer).
'in' is an insertion indicator.
'shifting' indicates anagramming the letters.
'dunes' anagrammed gives 'unsed'.
'ale' put inside 'unsed' is 'UNSEALED'.

(Another definition for unsealed that I've seen is " Open".)

I've seen this clue in The Times.

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