If you log in to an app -- YouTube TV, YouTube, other Google owned apps -- on the Roku device, it will show up there. If you don't log in to a Google app on the Roku device, it won't show. And, it will probably show by the Roku model number. I'm logged in to YouTube on my Roku Ultra, and it shows as 4660RW, since that's the model number. I'm also logged in on my Streambar, and it shows as 9102RW, since that's the model number.
But, to reiterate, you don't log in to the device. You log in to apps on the device, such as YouTube.
Roku Community Streaming Expert
Note: I am not a Roku employee.
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