1 files changed, 44 insertions, 0 deletions
diff --git a/Jellyfin.Server/Migrations/Routines/20260911120000_StripEmbeddedLinkedChildren.cs b/Jellyfin.Server/Migrations/Routines/20260911120000_StripEmbeddedLinkedChildren.cs
new file mode 100644
index 0000000000..f61e42337a
--- /dev/null
+++ b/Jellyfin.Server/Migrations/Routines/20260911120000_StripEmbeddedLinkedChildren.cs
@@ -0,0 +1,44 @@
+using Jellyfin.Database.Implementations;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Logging;
+
+namespace Jellyfin.Server.Migrations.Routines;
+
+/// <summary>
+/// Drops keys that no current property reads or writes from the serialized <c>BaseItems.Data</c> blob.
+/// </summary>
+[JellyfinMigration("2026-09-11T12:00:00", nameof(StripEmbeddedLinkedChildren))]
+internal class StripEmbeddedLinkedChildren : IDatabaseMigrationRoutine
+{
+    private readonly ILogger<StripEmbeddedLinkedChildren> _logger;
+    private readonly IDbContextFactory<JellyfinDbContext> _dbProvider;
+
+    public StripEmbeddedLinkedChildren(
+        ILoggerFactory loggerFactory,
+        IDbContextFactory<JellyfinDbContext> dbProvider)
+    {
+        _logger = loggerFactory.CreateLogger<StripEmbeddedLinkedChildren>();
+        _dbProvider = dbProvider;
+    }
+
+    /// <inheritdoc/>
+    public void Perform()
+    {
+        using var context = _dbProvider.CreateDbContext();
+
+        // json_valid guards the rare malformed blob: json_remove would abort the statement on it,
+        // and one bad row must not cost every other row the fix.
+        var updated = context.Database.ExecuteSqlRaw(
+            """
+            UPDATE "BaseItems"
+            SET "Data" = json_remove("Data", '$.LinkedChildren', '$.ExtraIds', '$.SupportsExternalTransfer')
+            WHERE "Data" IS NOT NULL
+              AND json_valid("Data") = 1
+              AND ("Data" LIKE '%"LinkedChildren"%'
+                OR "Data" LIKE '%"ExtraIds"%'
+                OR "Data" LIKE '%"SupportsExternalTransfer"%')
+            """);
+
+        _logger.LogInformation("Dropped dead keys from the serialized data of {Count} items", updated);
+    }
+}