As indicated in your screenshots, you have Aquatic Life v.3.0 build 9000013. On all my devices with this version number, it is available as both a screensaver and a channel. If you choose to use it as a screensaver, it automatically adds it as a channel. If you remove the Aquatic Life channel, it will remove the Aquatic Life as your preferred/active screensaver. (remains as available in popular screensaver, just no longer set as active.). If you choose to again set as active, it merely installs the channel again.
Earlier "versions" of the Aquatic Life v.3.x apparently installed both a channel and screensaver. Aquatic Life v.3.0 build 9000013 "fixed" this issue of seperate simulataneous channel and screensaver, depending on who you ask. Users at the time of release complained about the seperate channel loss/removal. (could only be used as screensaver, no seperate ability to launch as a channel).
So... it looks like v.3.0 build 9000013 has reverted back to its previous behavior. (earlier 3.x releases). Personally, does not bother me to have it hanging around as another channel icon on the screen. What one user sees as a programming bug, another user may see as an additional useful feature. (especially those who mourned its earlier loss).
And you are correct about your Ultra devices. If they are using the Aquatic Life v.13.0.90000013 (note the 13, not 3), then these will not show the additional channel/app.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
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