Handle thief following specific way of working (8)

I believe the answer is:

monicker

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'handle thief' is the definition.
'monicker' can be an answer for 'handle' (I've seen this before). I am not certain of the 'thief' bit.

'following specific way of working' is the wordplay.
'following' is a charade indicator (letters next to each other).
'specific' becomes 'nicker' (I am not sure about this - if you are sure you should believe this answer much more).
'way of working' becomes 'mo' (modus operandi).
'nicker' after 'mo' is 'MONICKER'.

Can you help me to learn more?

(Other definitions for monicker that I've seen before include "Name or nickname" , "Name (sl)" , "Handle" , "Nickname (slang)" .)

I've seen this clue in The Guardian.

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