[Issue]: [Regression] User-created playlists not accessible via CollectionView in v10.8.11

[Chaphasilor]

Please describe your bug

Any playlists manually created by a user (as opposed to automatically discovered from e.g. a m3u file) are not returned by the ID if the parentId is set to the ID of the CollectionView. Afaik, only CollectionViews of type Music make use of this feature in the web client.

Before Jellyfin 10.8.11, the parentId would be ignored when fetching Playlist items from the API, resulting in the request <baseUrl>/Users/<userId>/Items?IncludeItemTypes=Playlist&Recursive=true&StartIndex=0&ParentId=<musicTypeCollectionViewId> to return any created playlist (scanned, manually created within the Music CollectionView, as well as created in any other CollectionView like Shows).
This of course wasn't ideal either (I don't want to see a playlist of show episodes in my music client), and therefore this was "fixed" in #9909 and backported to 10.8.z in #9916.

Now only auto-discovered playlists are returned when performing the request above; the user-created playlists can only be found in the UserView of collectionType: playlist. If this behavior was by design, it would be extremely annoying when building music clients for Jellyfin, and would prevent separating music playlists from video playlists.

To reproduce:

1. Set up Jellyfin 10.8.11 (via docker)
2. Import at least a music library that contains at least one m3u playlist file
3. Jellyfin should auto-detect the playlist, and it should show up in the web client under Home > Music > Playlists
4. Create a new playlist and add at least one song to it
5. The newly created playlist is not shown under Home > Music > Playlists, but does show up under Home > Playlists

Jellyfin Version

Other

if other:

10.8.11

Environment

- OS: TrueNAS-SCALE-22.12.3.3
- Linux Kernel: ?
- Virtualization: Docker (k3s)
- Clients: Finamp 0.6.17, jellyfin-web 10.8.11
- Browser: Microsoft Edge Dev 119.0.2109.1
- FFmpeg Version: n/a
- Playback Method: n/a
- Hardware Acceleration: n/a
- GPU Model: n/a
- Plugins: none
- Reverse Proxy: none
- Base URL: none
- Networking: n/a
- Storage: host path / ZFS dataset

Jellyfin logs

issue doesn't show up in any logs

FFmpeg logs

No response

Please attach any browser or client logs here

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Code of Conduct

• I agree to follow this project's Code of Conduct

[BloodyIron]

Playlists created on Jellyfin stopped showing up in Finamp with Jellyfin server 10.8.11, but switched to the 10.8.10 docker image and the issue was addressed immediately. This looks to be a reliably provable regression with 10.8.11.