I have Roku for all my tv's...but also have a FireTV. I want to have OAN, which I subscribe to on Roku, but no idea how to get that to apply to the FireTV without getting another subscription, which I shouldn't have to do.
I can't speak to OAN specifically, but in general when you subscribe to a premium channel through a third party like Roku, Apple Tv, Fire TV, etc. your subscription is only accessable via that third party.
In order to access through a variety of devices you must subscribe directly with that channel on its web page. Then you can install the channel's app version for each device and log into it.
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