That "not available" message is misleading. The channel isn't compatible with the v11.5 Roku software update because it uses components that were completely removed. If it were to come back it would be Seagate (or someone else) that would have to make a version compatible with the Roku update. Roku wouldn't be the ones to do it.
If the Roku Media Player works with it then the Plex channel probably would as well. There may be other options out there that I'm not aware of as well.
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