^^ it's not a shadow but a background with curtains/a tile/another wall, lol
they had a background then decided to make it white, and thus cut her arm above the head (I noticed they cut her haircut too) and didn't blend the area around face to new white background properly. they just cut it and left it like this, I can't believe it!
very unprofessional!
when you do photoshop you can see 'crappy photoshop' really well
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