When the user profile page loads a thin horizontal line travels down?

In any of the profile pages I visit say for example https://help.zoho.com/portal/en/community/user/mmuthuraj, I see a thin curtains-down style horizontal line travels down the photo once after the image completes loading.

I am using FF. Anyone else facing this issue too?

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Deepak Vasudevan
http://thamizhththendral.blogspot.com/