Letters bring Frenchman trouble (4)

I believe the answer is:

mail

'letters' is the definition.
(I've seen this before)

'frenchman trouble' is the wordplay.
'frenchman' becomes 'm' (abbreviation for Monsieur - like 'Mr').
'trouble' becomes 'ail' (synonyms).
'm'+'ail'='MAIL'

'bring' acts as a link.

(Other definitions for mail that I've seen before include "Post or body armour" , "Letters - armour" , "letter?" , "Form of armour; post" , "American post from Lima" .)

I've seen this clue in The Mirror.

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