Noted at https://support.tclusa.com/23507-roku-tv/258975-how-to-connect-your-tcl-roku-tv-to-the-internet
I'd check your model again.
I have a TCL Roku TV (built-in WiFi) and a Comcast (no idea who the manufacturer is) modem/wireless router. I'm having issues with the WiFi connection dropping out with the router, so I'd like to try a wired connection.
Issue: The router has only Ethernet (output) ports, and the TV has only HDMI (input) ports. I have "cut the cord" and have no cable box.
Question: Is there an adapter or converter that would allow me to connect an Ethernet router port to an HDMI port on the TV?

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