Open one French saloon (5)

I believe the answer is:

unbar

'open' is the definition.
(unbarring is a kind of opening)

'one french saloon' is the wordplay.
'one french' becomes 'un' ('one' in French).
'saloon' becomes 'bar' (synonyms).
'un'+'bar'='UNBAR'

(Another definition for unbar that I've seen is " Free".)

I've seen this clue in the Sydney Morning Herald.

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