Happy working atmosphere (2,3)

I believe the answer is:

on air

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'happy' is the definition.
I know nothing about this answer so I can't tell whether this works.

'working atmosphere' is the wordplay.
'working' becomes 'on' (e.g. a machine is working or on).
'atmosphere' becomes 'air' (synonyms).
'on'+'air'='ON-AIR'

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(Other definitions for on air that I've seen before include "Transmitting now!" , "Cushioned" , "now showing" , "In the process of broadcasting - floating aloft?" , "Broadcasting studio sign" .)

I've seen this clue in The Guardian.

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