Enjoying short-term popularity after setback, government intervening between Brussels and Stormont? (2,5)
I believe the answer is:
in vogue
'enjoying short-term popularity' is the definition.
(in vogue means in fashion)
I cannot understand how the remainder of the clue works.
(Other definitions for in vogue that I've seen before include "'In the current fashion or style (2,5)'" , "A la mode, fashionable" , "Currently fashionable" .)