A "disconnected" Hisense TV found a way to connect itself to the internet.

Can somebody please explain how a Hisense TV is able to connect to the internet and update itself without having ever been connected to the internet? Literally the only thing that it's connected to is Roku through HDMI. Is Roku able to share its internet connection somehow? Shouldn't at least one of them be asking me for a permission to do this?

All the internet-related settings on the TV have been switched off and disabled. It's a 75" from A6 …

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