Yes, a system update did it. I didn't have to restart. The app reappeared after the update. I could listen to Spotify again. Didn't need to log in to the Spotify account either. Everything stayed as it was before.
The "Control by mobile apps" functionality is mostly broken - "disabled" only applies to third-party apps using the "Play on Roku"/ECP protocol/functionality, not to Roku apps or any DIAL protocol apps.
Spotify uses DIAL casting protocol on Roku, and RokuOS has no permission controls for it ("Control by mobile apps" doesnt apply).
Roku should have a DIAL access control, but they dont.
NetFlix, YouTube, YouTube TV, etc, use DIAL on Roku as well and would also be prevented from casting.
I don't believe the problem in a Spotify issue since I have no issues with it's operation on my iPad, iPhone or Asus laptop. I'm only experiencing the problem when trying to activate Spotify through my Roku stick. Roku is asking me to logon to Spotify even though I never logged off it. It shows my Facebook profile pic and expressly states "This account is linked with your Roku credentials." But clicking on the log-in toggle gets me nowhere. And Roku does not respond when I attempt to remove Spotify (to add it back in later). When I look for software update Roku tells me I'm up to date (and that even though Roku claims to check daily, the last update goes back to June 2021.)
@JimmieU it doesn't matter if the app works fine on other devices. It's not the same app, and not written in the same programming language. If everything else is working fine, then the problem is with the Spotify channel, and Spotify is the only one that can fix it. Roku does not create or support 3rd party channels, and they're almost all 3rd party channels.
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Seriously with this nonsense. It’s been two days now and your lack of response or acknowledging that there is an issue has me close to cancelling. Ive been a ROKU owner for over 25 years, and a Spotify user for about 10. Get your act together or I’m out. Which I’m sure with your lack of response, really means you honestly don’t care.