Instrument untangling long fur, help Manx (10)

I believe the answer is:

flugelhorn

'instrument' is the definition.
(flugelhorn is a kind of instrument)

'untangling long fur help manx' is the wordplay.
'untangling' indicates anagramming the letters.
'manx' means to remove the last letter (Manx cats have no tail).
'long'+'fur'+'help'='longfurhelp'
'longfurhelp' with its final letter taken off is 'longfurhel'.
'longfurhel' is an anagram of 'FLUGELHORN'.

(Another definition for flugelhorn that I've seen is " Brass instrument".)

I've seen this clue in The Guardian.

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