docs: Update migration doc

build/cSpell.json

@@ -124,6 +124,7 @@
 	"Authenticode",
 	"automagically",
 	"bluetoothdevice",
+	"browserwasm",
 	"commandbar",
 	"CLSID",
 	"datatransfer",

doc/articles/features/image.md

@@ -39,3 +39,17 @@ MyImage.UriSource = new BitmapImage { UriSource = new($"ms-appdata:///local/imag
 
 > [!IMPORTANT]
 > When using WinAppSDK Unpackaged mode, `ms-appdata:///` is not supported on `Image`. In this case, you can use [`BitmapImage.SetSourceAsync`](https://learn.microsoft.com/windows/windows-app-sdk/api/winrt/microsoft.ui.xaml.media.imaging.bitmapsource.setsourceasync) to set the image programmatically.
+
+## Gif Support
+
+Displaying animated GIFs is supported on:
+
+- netX.0-desktop (5.4 and later)
+- netX.0-windows
+- netX.0-browserwasm
+
+Unsupported targets, where only the first frame is shown, as of Uno Platform 5.4:
+
+- netX.0-ios
+- netX.0-android
+- netX.0-maccatalyst

doc/articles/features/windows-ui-markup-extensions.md

@@ -80,7 +80,45 @@ This class can be used as follows in the XAML:
 
 ### IRootObjectProvider
 
-Not supported as of Uno 4.3
+With access to IRootObjectProvider becomes possible for a Markup extension to browse the visual tree, starting from the root of the XAML file.
+
+This following example [from the WinUI specifications](https://github.com/microsoft/microsoft-ui-xaml-specs/blob/34b14114af141ceb843413bedb85705c9a2e9204/active/XamlServiceProvider/XamlServiceProviderApi.md#irootobjectprovider) give a glimpse of this feature.
+
+Using the following XAML:
+
+```csharp
+public class DynamicBindExtension : MarkupExtension
+{
+    public DynamicBindExtension(string propertyName)
+    {
+        _propertyName = propertyName;
+    }
+    string _propertyName;
+
+    public override object ProvideValue(IXamlServiceProvider serviceProvider)
+    {
+        var root = ((IRootObjectProvider)serviceProvider.GetService(typeof(IRootObjectProvider))).RootObject;
+        var info = root.GetType().GetProperty(_propertyName);
+        return info.GetValue(root);
+    }
+}
+```
+
+The following XAML will display “Page Tag”:
+
+```xml
+<Page Tag='Page tag' 
+      x:Class="App1.MainPage"
+      xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+      xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+      xmlns:local="using:App52"
+      Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
+
+    <Grid>
+        <TextBlock Text="{local:DynamicBind Tag}" />
+    </Grid>
+</Page>
+```
 
 ### IUriContext
 

doc/articles/features/working-with-xaml-hot-reload.md

@@ -103,7 +103,7 @@ Hot Reload features vary between platforms and IDE, you can check below the list
         </tr>
         <tr>
             <td>WinAppSDK</td>
-            <td>✅🐞</td><td>✅🐞</td>
+            <td>✅<sup><a href="#hr-footnotes">[5]</a></sup>🐞</td><td>✅🐞</td>
             <td>🔳</td><td>🔳</td>
             <td>🔳</td><td>🔳</td>
         </tr>
@@ -243,6 +243,7 @@ Legend:
 - [2]: Support is [not available](https://youtrack.jetbrains.com/issue/RIDER-53302/launchSettings.json-WSL2-command-support).
 - [3]: C# Hot Reload is affected by a [.NET Runtime issue](https://github.com/dotnet/android/issues/9120).
 - [4]: XAML Hot Reload is using the XAML Reader, [pending C# Hot Reload update](https://github.com/unoplatform/uno/issues/15918) and a [VS/VS Code update](https://developercommunity.visualstudio.com/t/net70-iosnet70-android-MetadataUpd/10279604).
+- [5]: C# Markup Hot Reload is supported when running in Unpackaged mode only
 
 ## Supported features per Platform
 

doc/articles/migrating-from-previous-releases.md

@@ -6,6 +6,20 @@ uid: Uno.Development.MigratingFromPreviousReleases
 
 This article details the migration steps required to migrate from one version to the next when breaking changes are being introduced.
 
+## Uno Platform 5.4
+
+Uno Platform 5.4 contains breaking changes for Uno.Extensions.
+
+### UWP Support for Uno.Extensions
+
+The [`Uno.Extensions`](https://aka.platform.uno/uno-extensions) compatibility with legacy UWP apps has been removed. If your app is UWP-based and uses Uno.Extensions, in order to migrate to Uno Platform 5.4, you can keep using [previous releases of Uno.Extensions](https://github.com/unoplatform/uno.extensions/releases), or [migrate your app to WinUI](https://platform.uno/docs/articles/updating-to-winui3.html).
+
+All the other features of Uno Platform 5.4 continue to be compatible with both UWP and WinUI apps.
+
+### Updates in Uno.Extensions.Reactive
+
+The generated code has changed, make sure to [review our docs to upgrade](xuid:Extensions.Migration.Reactive) to Uno Platform 5.4.
+
 ## Uno Platform 5.3
 
 Uno Platform 5.3 contains an improved template and Uno.SDK versioning, new default text font, and Rider support.