Mutilates corner in manuscript (7)

I believe the answer is:

mangles

'mutilates' is the definition.
('mangle' can be a synonym of 'mutilate')

'corner in manuscript' is the wordplay.
'corner' becomes 'angle' (eg a corner of a shape).
'in' is an insertion indicator.
'manuscript' becomes 'ms' (abbreviation for manuscript).
'angle' put within 'ms' is 'MANGLES'.

(Another definition for mangles that I've seen is " Mutilates".)

I've seen this clue in The Daily Express.

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