With a Roku device, you press the Home button on the Roku Remote to stop streaming content and return to Home Screen before powering down the TV. It will automatically go into a Sleep Mode after a bit on non-use.
If you have a Roku device powered by the TV's power port, then there also is the possibility that it may power down completely when the TV is powered down. With some TV power ports, the power remains on to connected HDMI devices, so for those, the Home button on Roku remote will need to be pressed to return to Home Screen and allow the Sleep mode to be activated.
With a Roku TV, best practice is to again press the Home button before powering down, but on the RokuTV, you can simply press the Power button and the RokuTV will power down completely or go into a low-power mode (if Fast Start is enabled).
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