What do you think this stain is?

[Scott Mac]

The stain on the bottom of the doorway.

Do you think it's mold under the paint?

The Water Closet is to the left of the door way. 

Vanity to the right, walk in shower with glass doors behind camera angle. 

I can see the painters painters painted over it, but it shows through, and it look rough like un-sanded wood putty.

Any thoughts?

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