Hi Sandrine welcome to the community.
It looks like the egg has got stuck to it's feathers while it has been brooding, I hope it made it home ok.
My Flickr photos
In reply to Alan.:
Oh dear, most unusual, wonder if the egg was okay.
Beauty is in the eye of the beholder.
Weird! You don't suppose it's been sitting on the ledge watching documentaries on penguins through the window?
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