fix(dto): prefer PlaylistsFolder primary image for playlists tiles

This patch fixes issue #16032 where the Playlists media folder ignored a user-uploaded Primary image and kept showing the generated collage. The root cause was DTO image precedence on UserView items for CollectionType.playlists. We now prefer the display parent (PlaylistsFolder) Primary image when available by clearing the UserView Primary tag and setting ParentPrimaryImageItemId/ParentPrimaryImageTag. Added tests cover both paths: parent custom image preferred, and fallback to existing UserView Primary when parent has none.

1 files changed, 15 insertions, 0 deletions

diff --git a/Emby.Server.Implementations/Dto/DtoService.cs b/Emby.Server.Implementations/Dto/DtoService.cs
index b392340f71..ac21c1c6d3 100644
--- a/Emby.Server.Implementations/Dto/DtoService.cs
+++ b/Emby.Server.Implementations/Dto/DtoService.cs
@@ -1363,6 +1363,21 @@ namespace Emby.Server.Implementations.Dto
 
         private void AddInheritedImages(BaseItemDto dto, BaseItem item, DtoOptions options, BaseItem? owner)
         {
+            if (item is UserView { ViewType: CollectionType.playlists } playlistsView
+                && options.GetImageLimit(ImageType.Primary) > 0
+                && !playlistsView.DisplayParentId.IsEmpty())
+            {
+                var displayParent = _libraryManager.GetItemById(playlistsView.DisplayParentId);
+                var displayParentPrimaryImage = displayParent?.GetImageInfo(ImageType.Primary, 0);
+
+                if (displayParentPrimaryImage is not null)
+                {
+                    dto.ImageTags?.Remove(ImageType.Primary);
+                    dto.ParentPrimaryImageItemId = displayParent!.Id;
+                    dto.ParentPrimaryImageTag = GetTagAndFillBlurhash(dto, displayParent, displayParentPrimaryImage);
+                }
+            }
+
             if (!item.SupportsInheritedParentImages)
             {
                 return;