Skip ZIndex from being serialized.

src/Persistence.Tests/Yaml/ValidSerializerTests.cs

@@ -181,12 +181,14 @@ public void Serialize_Should_FlattenGalleryTemplate(string expectedPath, bool is
                             properties: new()
                             {
                                 { "TemplateFill", "RGBA(0, 0, 0, 0)" },
+                                { "ZIndex", "1" },
                             }
                         ),
                         ControlFactory.Create("button12", template: "button",
                             properties: new()
                             {
                                 { "Fill", "RGBA(0, 0, 0, 0)" },
+                                { "ZIndex", "1" },
                             }
                         )
                     }
@@ -201,6 +203,42 @@ public void Serialize_Should_FlattenGalleryTemplate(string expectedPath, bool is
         sut.Should().Be(expectedYaml);
     }
 
+    [TestMethod]
+    [DataRow(@"_TestData/ValidYaml{0}/ZIndexOrdering/with-addpropertiestoparents-control.pa.yaml", true)]
+    [DataRow(@"_TestData/ValidYaml{0}/ZIndexOrdering/with-addpropertiestoparents-control.pa.yaml", false)]
+    public void Serialize_Should_FlattenGalleryTemplateWithoutZIndex(string expectedPath, bool isControlIdentifiers)
+    {
+        var graph = ControlFactory.Create("Gallery1", template: "gallery",
+                   properties: new()
+                    {
+                        { "Items", "Accounts" },
+                    },
+                    children: new List<Control>()
+                    {
+                        ControlFactory.Create("GalleryTemplate1", template: "galleryTemplate",
+                            properties: new()
+                            {
+                                { "TemplateFill", "RGBA(0, 0, 0, 0)" },
+                                { "ZIndex", "1" },
+                            }
+                        ),
+                        ControlFactory.Create("Button1", template: "button",
+                            properties: new()
+                            {
+                                { "Fill", "RGBA(0, 0, 0, 0)" },
+                                { "ZIndex", "1" },
+                            }
+                        )
+                    }
+               );
+
+        var serializer = CreateSerializer(isControlIdentifiers);
+
+        var sut = serializer.SerializeControl(graph).NormalizeNewlines();
+        var expectedYaml = File.ReadAllText(GetTestFilePath(expectedPath, isControlIdentifiers)).NormalizeNewlines();
+        sut.Should().Be(expectedYaml);
+    }
+
     [TestMethod]
     [DataRow(@"_TestData/ValidYaml{0}/BuiltInControl/with-variant.pa.yaml", "SuperButton", null, true)]
     [DataRow(@"_TestData/ValidYaml{0}/BuiltInControl/with-variant.pa.yaml", "SuperButton", null, false)]

src/Persistence.Tests/_TestData/ValidYaml-CI/ZIndexOrdering/with-addpropertiestoparents-control.pa.yaml

@@ -0,0 +1,10 @@
+Gallery1:
+  Control: Gallery
+  Properties:
+    Items: =Accounts
+    TemplateFill: =RGBA(0, 0, 0, 0)
+  Children:
+  - Button1:
+      Control: Button
+      Properties:
+        Fill: =RGBA(0, 0, 0, 0)

src/Persistence.Tests/_TestData/ValidYaml/ZIndexOrdering/with-addpropertiestoparents-control.pa.yaml

@@ -0,0 +1,10 @@
+Control: Gallery
+Name: Gallery1
+Properties:
+  Items: =Accounts
+  TemplateFill: =RGBA(0, 0, 0, 0)
+Children:
+- Control: Button
+  Name: Button1
+  Properties:
+    Fill: =RGBA(0, 0, 0, 0)

src/Persistence/Yaml/ControlFormatter.cs

@@ -20,7 +20,7 @@ public static T BeforeSerialize<T>(this T control) where T : Control
         _ = control ?? throw new ArgumentNullException(nameof(control));
 
         var childrenToRemove = (control.Children ?? Enumerable.Empty<Control>()).Where(c => c.Template.AddPropertiesToParent).ToList();
-        var propertiesToMerge = childrenToRemove.SelectMany(c => c.Properties).ToList();
+        var propertiesToMerge = childrenToRemove.SelectMany(c => c.Properties.Where(p => p.Key != PropertyNames.ZIndex)).ToList();
 
         var isGroupContainer = control.Template.Name == BuiltInTemplates.GroupContainer.Name;