What does the ribbon cable at the right go to?. I was thinking it could be a transformer powering some type of display, such as the heater in a florescent display.
It goes to the incoming power side. Specifically, those back legs go to the anodes of two diodes. There's fore and aft continuity on the left and right respectively. There's also no continuity left or right. It acts like an inductor coil would imo.
I thought it was one of these. A common mode choke. Note only the corner pins are used. The traces going to the part look thick. Ohm meter the pins. I think you will see less than one ohm from pin to pin.
A common mode choke from https://www.digikey.com/en/supplier-centers/wurth-electronics.