Bores backing flag comprehending talks (7)

I believe the answer is:

gasbags

'bores' is the definition.
(gasbag is a kind of bore)

'backing flag comprehending talks' is the wordplay.
'backing' is a reversal indicator.
'flag' becomes 'sag' (synonyms).
'comprehending' is an insertion indicator (comprehend can mean include or contain).
'talks' becomes 'gabs'.
'sag' enclosing 'gabs' is 'sgabsag'.
'sgabsag' back-to-front is 'GASBAGS'.

(Another definition for gasbags that I've seen is " Talkative people".)

I've seen this clue in The Telegraph.

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