.NET 11 Preview 4

What's Changed

• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14242
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14243
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14246
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14250
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14254
• Fix bugs in the shared Clipboard code for WPF #11401 and #11402. by @JeremyKuhne in #14257
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14258
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14274
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14281
• Run the issue-labeler over pull requests using polling by @jeffhandley in #14280
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14282
• Add codeql config to mass suppress certain not-applicable rules by @GrabYourPitchforks in #14240
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14289
• Fix GC hole in EnumExtensions.ChangeFlags by @Copilot in #14290
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14294
• Updating build agent image to use VS2026 by @Shyam-Gupta in #14299
• Fix typo in codeql yml by @GrabYourPitchforks in #14300
• Updating build agent image to VS 2026 Preview scout by @Shyam-Gupta in #14321
• Move some usings to globals by @JeremyKuhne in #14331
• Fix for OOM exception while running Analyzer tests on x86 platform by @Shyam-Gupta in #14328
• Remove unused code by @JeremyKuhne in #14335
• Skipping Analyzer tests on x86 due to OOM exception. by @Shyam-Gupta in #14348
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14334
• Introduce Copilot Skills to the WinForms Runtime repo by @KlausLoeffelmann in #14353
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14355
• Remove the central TargetFramework property by @JeremyKuhne in #14357
• Add System.Diagnostics.DiagnosticSource version by @JeremyKuhne in #14358
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14361
• Fix for intermittent test failure on x86 platform 'BindingContext_UpdateBinding_UpdateListBindingWithoutDataMember_Success' by @Shyam-Gupta in #14359
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14368
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14373
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14380
• Add shared project for .NET Framework polyfills by @JeremyKuhne in #14371
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14387
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14391
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14395
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14396
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14399
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14401
• Multi-target System.Private.Windows.Core by @JeremyKuhne in #14384
• Fix issue 14071: ComboBox.ObjectCollection.CopyTo(Array destination, int index) copies Entry object, not inner item by @SimonZhao888 in #14075
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14405
• Fix InvalidCastException in Control.OnHandleDestroyed for non-ControlAccessibleObject by @LeafShi1 in #14295
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14409
• Add documentation and in-code awareness for shared WinForms/WPF clipboard/OLE infrastructure by @Copilot in #14306
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14419
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14426
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14431
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14432
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14433
• Update repo Copilot skills by @KlausLoeffelmann in #14428
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14437
• Adding NuGet package for Microsoft.Private.Windows.Core assembly by @Shyam-Gupta in #14429
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14443
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14444
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14446
• Updating TFM for .NET Framework assembly from net472 to net481 by @Shyam-Gupta in #14450
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14456
• Fix Clipboard.GetDataObject().GetImage regression for bitmap images by @LeafShi1 in #14427
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14464
• Adding new skills for Build, Test and downloading correct .NET SDK by @Shyam-Gupta in #14451
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14470
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14476
• Fix issue 14471: The WinformsControlTest project exited when clicking Column2 header after clicked the Change DGV font button by @SimonZhao888 in #14477
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14479
• Add scheduled workflow to auto-fix NuGet.config packageSource key mismatch in release/10.0 PRs by @Copilot in #14480
• Pin System.Formats.Nrbf and its transitive dependencies to 10.0.4 release for .NET Framework by @Shyam-Gupta in #14487
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14493
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14496
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14498
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14499
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14503
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14510
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14513
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14518
• Fix issue 14489: ToolStrip (TabStop=true) intercepts arrow keys after tab navigation, preventing TreeView from handling them by @SimonZhao888 in #14491
• Fix issue 14458: Clipboard.GetText(TextDataFormat.Rtf) does not retrieve RTF that lacks a null terminating character by @SimonZhao888 in #14461
• Fix ToolStripDropDownMenu scroll boundary handling to prevent out-of-range and unintended dropdown dismissal by @LeafShi1 in #14490
• Fix AnchorLayoutV2 deferred anchor initialization when replacing anchored controls during suspended layout by @LeafShi1 in #14505
• Fix stale ILLink substitution for removed non-existent PictureBox method “LoadImageViaWebClient” by @LeafShi1 in #14511
• Update the link of the "APIs of DotNet" in porting-guidelines.md by @LeafShi1 in #14179
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14524
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14526
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14533
• [main] Source code updates from dotnet/dotnet by @dotnet-maestro[bot] in #14534

Full Changelog: v11.0.0-preview.1.26104.118...v11.0.0-preview.4