10.0.4

Added

• Add unit tests for Reconciler.update, covering that it forwards exactly one diff to IViewNode.ApplyDiff, correctly reports scalar-attribute added/unchanged/changed cases, and handles a missing previous widget and an attribute-less widget pair (Repo Assist, #1341).
• Add unit tests covering WidgetDiff.ScalarChanges diffing (Added/Removed/Updated cases, empty prev/next, and the SkipRepeatingScalars duplicate-key behavior) (Repo Assist, #1311).
• Add unit tests for WidgetDiff.EnvironmentChanges, covering empty prev/next, all-Added/all-Removed cases, Updated on differing values, no-op on identical values, disjoint key sets, and the SkipRepeatingScalars duplicate-key dedup behavior (Repo Assist, #1312).
• Add unit tests for WidgetDiff.WidgetChanges, covering Added/Removed/Updated/ReplacedBy cases, empty prev/next, no-op on identical widgets, canReuseView true/false branching, and disjoint attribute sets (Repo Assist, #1316).
• Add unit tests for WidgetDiff.WidgetCollectionChanges and WidgetDiff.WidgetCollectionItemChanges diffing, covering attribute-level added/removed/updated collection attributes and item-level insert/replace/update/remove behavior for collections of differing lengths (Repo Assist, #1332).

Changed

• Simplify Cmd.map's closure composition to avoid allocating an extra intermediate function per effect on every call (Repo Assist, #1357).
• Implement CollectionBuilder.YieldFrom using MutStackArray1.addMut directly (addressing a TODO left in the code), avoiding the intermediate Seq.map/Seq.toArray allocations previously used to compile a sequence of widgets (Repo Assist, #1357).
• Revise the Windows development instructions in the MAUI tutorial and get-started guide, the MAUI/Avalonia tutorials and get-started guides, and the migration guide, and update the website index page and header.
• Change the MAUI template (Fabulous.MauiControls.Templates) to generate an unpackaged Windows project by default: NewApp.fsproj now sets WindowsPackageType=None with the FS0226 workaround (WindowsAppSdkUndockedRegFreeWinRTInitialize=false), and Properties/launchSettings.json uses the Project command instead of MsixPackage. F5 debugging in Visual Studio and dotnet run now work on Windows without manual edits. This only affects projects created with this template version or later; projects generated earlier keep their current setup and can be converted by hand as described in the MAUI tutorial. To use MSIX packaging in a new project, set WindowsPackageType=MSIX and use MsixPackage in launchSettings.json (#1408, #1409).
• Update the MAUI tutorial for the unpackaged Windows default: keep the manual conversion steps for projects created before 10.0.4, fix the "Why not packaged (MSIX)?" anchor links, and document how to switch back to a packaged build (#1410).
• Update the FSharp.Maui.WinUICompat README to reflect that the Fabulous MAUI template now generates an unpackaged Windows project by default, while the stock MAUI template and earlier Fabulous templates still use MsixPackage (#1412).
• Change the MAUI samples to build as unpackaged Windows applications, matching the updated MAUI template: each sample's .fsproj now sets WindowsPackageType=None with the FS0226 workaround, and Properties/launchSettings.json uses the Project command instead of MsixPackage (Repo Assist, #1411, #1413).

Fixed

• Correct the Cmd module migration section in docs/guides/migration.md (Repo Assist, #1391).