Disapproval for Mister Barking's promotional activity (10)

I believe the answer is:

boosterism

'promotional activity' is the definition.

'disapproval for mister barking's' is the wordplay.
'disapproval' becomes 'boos' (a boo is a sound of disapproval).
'for' says to put letters next to each other.
'barking's' indicates an anagram (UK slang for mad).
'mister' is an anagram of 'terism'.
'boos'+'terism'='BOOSTERISM'

I've seen this clue in The Guardian.

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