As one viewer punned: 'Firefox has encountered an unexpected problem with your version of windows'.
The fox seems to enjoy its starring role, eyeballing the camera and savouring each lick, looking as though it is sticking its tongue out for its audience.
More than 219,000 YouTube users have so far viewed the clip of the cheeky animal, called 'stupid fox' in Russian.
Stupid it may be, but with its long pink tongue and high-pitched yelping noises, no-one would want to be the other side of the glass.
via Cheeky window-licking fox becomes an internet sensation | Mail Online.