Fighting in an ale bar? (6,6)

I believe the answer is:

bitter strife

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'fighting' is the definition.
I don't know anything about this answer so I can't tell whether this works.

'an ale bar?' is the wordplay.
'an ale' becomes 'bitter' (synonyms).
'bar?' becomes 'strife' (I can't explain this - if you can you should believe this answer much more).
'bitter'+'strife'='BITTER STRIFE'

'in' is the link.

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I've seen this clue in the Evening Standard.

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