Do French wear pants from now on? (12)

I believe the answer is:

henceforward

'from now on?' is the definition.
(I've seen this before)

'do french wear pants' is the wordplay.
'pants' indicates anagramming the letters (UK informal term for 'nonsense' or 'rubbish').
'do'+'french'+'wear'='dofrenchwear'
'dofrenchwear' is an anagram of 'HENCEFORWARD'.

(Another definition for henceforward that I've seen is " In future".)

I've seen this clue in The Telegraph.

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