Merge pull request #3441 from MicrosoftDocs/user/mikehoffms/wv2-relnotes-may-2025-prerelease (#3448)

WebView2 Release Notes for May 2025 Prerelease SDK

Co-authored-by: Michael Hoffman <v-mihoffman@microsoft.com>

Author: captainbrosset

microsoft-edge/webview2/release-notes/index.md

@@ -6,7 +6,7 @@ ms.author: msedgedevrel
 ms.topic: conceptual
 ms.service: microsoft-edge
 ms.subservice: webview
-ms.date: 05/05/2025
+ms.date: 05/12/2025
 ---
 # Release Notes for the WebView2 SDK
 
@@ -90,6 +90,68 @@ Use this API to manage iframe tracking on a page that contains multiple levels o
 <!-- end of May 2025 Release SDK -->
 
 
+<!-- May 2025 Prerelease SDK -->
+<!-- ====================================================================== -->
+## 1.0.3296-prerelease
+
+Release Date: May 12, 2025
+
+[NuGet package for WebView2 SDK 1.0.3296-prerelease](https://www.nuget.org/packages/Microsoft.Web.WebView2/1.0.3296-prerelease)
+
+For full API compatibility, this Prerelease version of the WebView2 SDK requires the WebView2 Runtime that ships with Microsoft Edge version 137.0.3296.0 or higher.
+
+
+<!-- ------------------------------ -->
+#### Experimental APIs
+
+No Experimental APIs have been added in this Prerelease SDK.
+
+
+<!-- ------------------------------ -->
+#### Promotions
+
+The following APIs have been promoted from Experimental to Stable in this Prerelease SDK.
+
+
+<!-- ---------- -->
+###### Set default background color on WebView2 initialization (DefaultBackgroundColor API)
+
+The DefaultBackgroundColor API allows users to set the `DefaultBackgroundColor` property at initialization.  This prevents a disruptive white flash during the WebView2 loading process.
+
+##### [.NET/C#](#tab/dotnetcsharp)
+
+* `CoreWebView2ControllerOptions` Class:
+   * [CoreWebView2ControllerOptions.DefaultBackgroundColor Property](/dotnet/api/microsoft.web.webview2.core.corewebview2controlleroptions.defaultbackgroundcolor?view=webview2-dotnet-1.0.3296-prerelease&preserve-view=true)
+
+##### [WinRT/C#](#tab/winrtcsharp)
+
+* `CoreWebView2ControllerOptions` Class:
+   * [CoreWebView2ControllerOptions.DefaultBackgroundColor Property](/microsoft-edge/webview2/reference/winrt/microsoft_web_webview2_core/corewebview2controlleroptions?view=webview2-winrt-1.0.3296-prerelease&preserve-view=true#defaultbackgroundcolor)
+
+##### [Win32/C++](#tab/win32cpp)
+
+* [ICoreWebView2ControllerOptions3](/microsoft-edge/webview2/reference/win32/icorewebview2controlleroptions3?view=webview2-1.0.3296-prerelease&preserve-view=true)
+  * [ICoreWebView2ControllerOptions3::get_DefaultBackgroundColor](/microsoft-edge/webview2/reference/win32/icorewebview2controlleroptions3?view=webview2-1.0.3296-prerelease&preserve-view=true#get_defaultbackgroundcolor)
+  * [ICoreWebView2ControllerOptions3::put_DefaultBackgroundColor](/microsoft-edge/webview2/reference/win32/icorewebview2controlleroptions3?view=webview2-1.0.3296-prerelease&preserve-view=true#put_defaultbackgroundcolor)
+ 
+---
+
+
+<!-- ------------------------------ -->
+#### Bug fixes
+
+
+<!-- ---------- -->
+###### Runtime-only
+
+* Fixed the **Find** bar no longer appearing after the window is shifted.
+* Fixed a bug where the app wasn't able to cancel navigation to login pages via the `NavigationStarting` event.
+* Fixed an issue where downloads from within the default browser frame didn't complete.  ([Issue #5196](https://github.com/MicrosoftEdge/WebView2Feedback/issues/5196))
+* Fixed an issue where the pipe name was incorrectly returned, leading to a crash in some UWP apps. 
+
+<!-- end of May 2025 Prerelease SDK -->
+
+
 <!-- Apr 2025 Release SDK -->
 <!-- ====================================================================== -->
 ## 1.0.3179.45