diff --git a/tests/Squidex.Domain.Apps.Core.Tests/Model/Contents/WorkflowsJsonTests.cs b/tests/Squidex.Domain.Apps.Core.Tests/Model/Contents/WorkflowsJsonTests.cs
new file mode 100644
index 000000000..52074fee1
--- /dev/null
+++ b/tests/Squidex.Domain.Apps.Core.Tests/Model/Contents/WorkflowsJsonTests.cs
@@ -0,0 +1,26 @@
+// ==========================================================================
+//  Squidex Headless CMS
+// ==========================================================================
+//  Copyright (c) Squidex UG (haftungsbeschraenkt)
+//  All rights reserved. Licensed under the MIT license.
+// ==========================================================================
+
+using FluentAssertions;
+using Squidex.Domain.Apps.Core.Contents;
+using Xunit;
+
+namespace Squidex.Domain.Apps.Core.Model.Contents
+{
+    public class WorkflowsJsonTests
+    {
+        [Fact]
+        public void Should_serialize_and_deserialize()
+        {
+            var workflow = Workflows.Empty.Set(Workflow.Default);
+
+            var serialized = workflow.SerializeAndDeserialize();
+
+            serialized.Should().BeEquivalentTo(workflow);
+        }
+    }
+}
diff --git a/tests/Squidex.Domain.Apps.Core.Tests/Model/Contents/WorkflowsTests.cs b/tests/Squidex.Domain.Apps.Core.Tests/Model/Contents/WorkflowsTests.cs
new file mode 100644
index 000000000..37ce537c4
--- /dev/null
+++ b/tests/Squidex.Domain.Apps.Core.Tests/Model/Contents/WorkflowsTests.cs
@@ -0,0 +1,37 @@
+// ==========================================================================
+//  Squidex Headless CMS
+// ==========================================================================
+//  Copyright (c) Squidex UG (haftungsbeschraenkt)
+//  All rights reserved. Licensed under the MIT license.
+// ==========================================================================
+
+using System;
+using Squidex.Domain.Apps.Core.Contents;
+using Xunit;
+
+#pragma warning disable SA1310 // Field names must not contain underscore
+
+namespace Squidex.Domain.Apps.Core.Model.Contents
+{
+    public class WorkflowsTests
+    {
+        private readonly Workflows workflows_0 = Workflows.Empty;
+
+        [Fact]
+        public void Should_provide_default_workflow_if_none_found()
+        {
+            var workflow = workflows_0.GetFirst();
+
+            Assert.Same(Workflow.Default, workflow);
+        }
+
+        [Fact]
+        public void Should_set_workflow_with_empty_guid()
+        {
+            var workflows_1 = workflows_0.Set(Workflow.Default);
+
+            Assert.Single(workflows_1);
+            Assert.Same(Workflow.Default, workflows_1[Guid.Empty]);
+        }
+    }
+}
diff --git a/tests/Squidex.Domain.Apps.Core.Tests/TestUtils.cs b/tests/Squidex.Domain.Apps.Core.Tests/TestUtils.cs
index 9452cf681..e6e9b36d5 100644
--- a/tests/Squidex.Domain.Apps.Core.Tests/TestUtils.cs
+++ b/tests/Squidex.Domain.Apps.Core.Tests/TestUtils.cs
@@ -38,7 +38,7 @@ namespace Squidex.Domain.Apps.Core
 
             var serializerSettings = new JsonSerializerSettings
             {
-                SerializationBinder = new ReadOnlyDictionaryBinder(new TypeNameSerializationBinder(typeNameRegistry)),
+                SerializationBinder = new TypeNameSerializationBinder(typeNameRegistry),
 
                 ContractResolver = new ConverterContractResolver(
                     new AppClientsConverter(),