Pictures are low-resolution
The pictures online are all extremely low-resolution and pixelated. Facebook seems to be the site I notice it most on. It's like all the pictures were taken with early 2000's camera phones. I know the pictures don't look that bad.
Alla svar (3)
Does that also happen if you open an image directly in a browser tab?
Do you have an ISP or use a low bandwidth (wireless) connection that could cause it?
See also:
I tried opening a picture directly, and the pictures still come out pixelated. Facebook seems to be the only site I'm having problems with, but I'm chalking that up to possible image type discrepancies.
Reset the page zoom on pages that cause problems: View > Zoom > Reset (Ctrl+0 (zero); Cmd+0 on Mac)