"Any expert opinion of whether this a camera? Perhaps @SingaporeAir could clarify how it is used?"
He received an almost immediate response from Singapore Airlines, who confirmed it was a camera but said it was not switched on and there were no plans to use them.
"We would like to share that some of our newer in-flight entertainment systems provided by the original equipment manufacturers do have a camera embedded in the hardware," the carrier tweeted.
"These cameras have been disabled on our aircraft, and there are no plans to develop any features using the cameras."
After another Twitter user asked the airline why the cameras were there if there were no plans to use then, Singapore Airlines responded again.
"These cameras on our newer IFE (in-flight entertainment) systems were provided by the original equipment manufacturers. We have no plans to enable or develop any features using the cameras."
It made one commentator wonder if cameras could be used in the future, since IFE systems were being manufactured with them installed.
Claire Reilly, an editor for electronics website CNET, wrote in a blog post: "You can bet that the 'original equipment manufacturers' who installed these cameras weren't trying to meet a growing demand for seat-cam footage of tired plane passengers.
"We aren't livestreamed entertainment in this grim, dystopian future: We are an audience to be marketed to, data to be mined and a captive set of eyeballs to be coerced.
"Cameras are in our advertising billboards, in our devices and on every second street corner, tracking our movements and slowly building up a picture of our lives in minute-by-minute real time. Add airplanes to the mix and you have a terrifying new way to calculate your social credit score."