Feature of many a pub upsetting to barman indeed

I believe the answer is:

one-armed bandit

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'feature of many a pub' is the definition.
I can't tell whether this defines the answer.

'upsetting to barman indeed' is the wordplay.
'upsetting' indicates an anagram.
'to'+'barman'+'indeed'='tobarmanindeed'
'tobarmanindeed' anagrammed gives 'ONE-ARMED BANDIT'.

Can you help me to learn more?

(Other definitions for one-armed bandit that I've seen before include "Bend" , "Gambling machine" .)

I've seen this clue in The Telegraph.

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