Performed in tandem fitting concert finale alongside online lecture (7)

I believe the answer is:

duetted

'performed in tandem' is the definition.

'fitting concert finale alongside online lecture' is the wordplay.
'fitting' becomes 'due'.
'finale' indicates one should take the final letters.
'alongside' is a charade indicator (letters next to each other).
'online lecture' becomes 'ted' (TED Talks).
The last letter of 'concert' is 't'.
'due'+'t'+'ted'='DUETTED'

I've seen this clue in The Independent.

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