Document Cosmos support for complex types (EF Core 11)

entity-framework/core/what-is-new/ef-core-11.0/whatsnew.md

@@ -77,6 +77,12 @@ This enhancement removes a significant limitation when modeling complex domain h
 
 For more information on inheritance mapping strategies, see [Inheritance](xref:core/modeling/inheritance).
 
+<a name="complex-types-cosmos"></a>
+
+### Complex types in Azure Cosmos DB
+
+Complex types are now fully supported in the Azure Cosmos DB provider, embedded as nested JSON objects or arrays. For more information, [see the Cosmos DB section below](#cosmos-complex-types).
+
 ## LINQ and SQL translation
 
 <a name="linq-maxby-minby"></a>
@@ -106,6 +112,38 @@ Similarly, `MinByAsync` orders ascending and returns the element with the minimu
 
 ## Cosmos DB
 
+<a name="cosmos-complex-types"></a>
+
+### Complex types
+
+EF Core [complex types](xref:core/what-is-new/ef-core-10.0/whatsnew#complex-types) are now fully supported in the Azure Cosmos DB provider; they are embedded as nested JSON objects (or arrays, for collections) within the owning document, with support for queries, inserts, and updates.
+
+For example, the following configures `ShippingAddress` as a complex type:
+
+#### [Fluent API](#tab/fluent-api)
+
+```csharp
+modelBuilder.Entity<Order>()
+    .ComplexProperty(o => o.ShippingAddress);
+```
+
+#### [Data Annotations](#tab/data-annotations)
+
+```csharp
+[ComplexType]
+public class ShippingAddress
+{
+    public required string Street { get; set; }
+    public required string City { get; set; }
+}
+```
+
+***
+
+Complex types are generally a better fit than owned types when mapping to JSON documents: unlike owned types, complex types have value semantics and no identity, which means they work better in scenarios such as comparing two embedded objects within the same document.
+
+This feature was contributed by [@JoasE](https://github.com/JoasE) - many thanks!
+
 <a name="cosmos-transactional-batches"></a>
 
 ### Transactional batches