a better option that doesn't require specific steps depending on your TV model is just to use a small media PC strapped to the back. and then disable network access for the TV. the benefit of this is that when you buy a new PC, you don't have to do any research to find out which ones you can jailbreak, because any TV works.

you can then control the media PC with a cheap Bluetooth keyboard/touchpad combo. there are plenty of models available that are no bigger than a large remote and have excellent battery life.