When I go to an artist page > liked songs, the list contains songs from that artist that I haven't liked. It looks like this list doesn't just contain all the individually liked songs from an artist, but also every song from every album you've liked by that artist, regardless of whether the song itself is liked.
For example, if I like an album with 12 songs in it and then individually like 11 out of the 12 songs on the album, the 12th song will still appear in the artist > liked list. If I unlike the album itself, but leave all the liked songs intact, and go back to the artist > liked list, the 12th song will not be there. If I tap on the three dots next to an unliked song in this list, it'll show that it hasn't been liked and it doesn't show up in any other lists of liked songs.
I would expect that this list would show only songs that have directly been liked, and not all of these extra songs. It kind of defeats the purpose of having this feature to begin with, given that it's the only way to get a list of all liked songs from a specific artist.
I tried to compare functionality with the Mac desktop application, but that doesn't even have the all like songs by an artist option on the artist page to begin with.
On mobile - Liking an Album would add all the tracks from that album to the Liked Songs on Artist page. The songs won't be added directly to your Liked Songs playlist. This was something which many users requested in the past.
The functionality of the app differs on different platforms and the UI is different, so it's to be expected that you don't find the same menus across platforms.
Hope this clears things up. Don't hesitate to reach out again if you have questions.
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