There's a ton of web sites that claim to explain how to watch "something" on a Roku. In every case I've seen, the only way it works is to screen mirror a computer, phone or tablet to the Roku. If there is no app/channel in the Roku channel store, there is zero way to watch something that isn't there. On occasion something like a podcast might be available within a different app/channel, but the article would need to state that clearly.
You cannot "sideload" an app that isn't available in the Roku channel store. You cannot "jailbreak" a Roku to do something outside their closed environment.
Dan
Roku Community Streaming Expert
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