Internet broadcaster's banner (8)
I believe the answer is:
streamer
I believe this is a double definition.
'internet broadcaster's' is the first definition.
(someone who streams online)
'banner' is the second definition.
(both can mean a flag)
(Other definitions for streamer that I've seen before include "Long flag -- bad cold" , "terrible cold?" , "It blows in the wind" , "Long 23 ac or ribbon" , "Long narrow ribbon for er, master" .)