Grey out songs in queues that are not available (or don’t show them at all?)
Currently, queues also show songs that are not available (e.g. provider disabled). This is weird when clicking on them because they fail to play. Disabling playback or at least visually hinting that these songs are not playable, would solve this.
Cleaner usage of queues.
There’s no notion of disabled provider so not sure what you mean.
In all cases the items in the queue are not yet resolved so no way to know if they are playable or not, and no way to know if they will be playable when the queue reach that point in time too.
Ok, maybe I should explain a little bit better. Let’s say I have a playlist with some songs that are not cached and some that are. When I now disconnect the source e.g. Jellyfin or whatever, the non-cached songs in the playlist are greyed out while the cached ones are still visible. This feature would be great to have in the queues as well. You cannot play those songs so you should not be able to select them from the queue.
Well, I don’t know how it works under the hood. But if you know the playable status of each song (which you probably need to know for the playlists) then you could also look up that availability status for songs in the queues. But I might be wrong here of course.
You are wrong 
As said the songs are not yet resolved in the queue, so the app does not know yet if the song can be played or not.
That’s how Symfonium can handle very very large queues without issues.
That’s unfortunate. Maybe it would be possible to resolve only the first 10 (maybe even larger? idk what number would be best here) songs of each queue. That way, one would have the best of both worlds.
One would have your very very large efficient queues, but also unavailable songs could be automatically skipped.
The songs are already skipped when reached if the provider is not accessible and no offline cache.
If you see otherwise open an issue with logs and details to repro.
Then I will do that 