Idle on the screen (4)
I believe the answer is:
eric
'idle on the screen' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for eric that I've seen before include "Ernie's comic partner" , "---- Roberts, actor brother of Julia" , "--, or Little by Little (Dean Farrar)" , "Boy's name" , "---- Cantona, Manchester Utd favourite of the 1990s" .)