They are two different subscriptions and one login won't work on the other. The one "on Roku" will only work on Roku devices. The content available may or may not be identical. Most here would strongly recommend not subscribing to anything through a third party like Roku, Amazon, Apple, etc. as most third party subscriptions come with restrictions and you're just introducing another layer of frustration when something goes wrong, but you'll have to decide for yourself at the end of the year if it was worth it since subscriptions are prepaid and nonrefundable.
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