Why is my gf seeing a localhost self signed certificate when going to netflix?

Recently my gf told me she was receiving errors when trying to go to netflix. I took a look and the certificate is super wierd saying it is self signed. Why could this be happening? She only uses the computer on our home wifi. She does not know how to self sign certificates so there is no way she did that herself either. I can’t for the life of me figure out the reason that is showing up and I’m concerned because that is a pretty bizarre thing to see… I don’t know if she has been MITM but I don’t see how that is possible when she is trying to access netflix through our home network. Our home network is a 15 character password. What are some reason’s this could be happening and what can I do to investigate this?

See below screen shot.

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