Add Microsoft Store color appearance troubleshooting documentation

[Copilot]

Addresses a documentation gap where developers experience different app background colors between the Microsoft Store web version and the Store app, with no existing guidance on why this occurs or how to resolve it.

Problem

Developers report that their UWP apps display custom background colors correctly in the web version of the Microsoft Store but show as gray (#464646) in the Microsoft Store app on Windows. The existing documentation mentions the default gray color but doesn't explain the discrepancy between different Store contexts or provide troubleshooting guidance.

Solution

New Documentation Added

uwp/launch-resume/microsoft-store-color-appearance-issues.md - Comprehensive troubleshooting guide that:

• Explains why the Microsoft Store app and web version render colors differently
• Provides step-by-step manifest validation and troubleshooting
• Includes practical examples using real developer scenarios (e.g., BackgroundColor="#0ab68e")
• Covers color format validation, accessibility considerations, and known limitations
• Offers workarounds for persistent issues

Enhanced Existing Documentation

Updated add-a-splash-screen.md:

> [!NOTE]
> The background color you set here also affects how your app appears in the Microsoft Store. 
> If you experience issues where your app shows as gray in the Microsoft Store app but displays 
> your custom color in the web version, see [Troubleshoot Microsoft Store app color and appearance issues]...

Updated splash-screens.md with reference to the new troubleshooting guide in the topic table.

Updated uwp/develop/toc.yml to include the new documentation in the splash screens section.

Key Features

• Addresses real developer pain points with specific examples and scenarios
• Explains the technical why behind Store app vs web rendering differences
• Provides actionable solutions including manifest validation and republishing steps
• Maintains consistency with existing documentation style and cross-references
• Covers edge cases like accessibility, theming, and platform variations

This documentation fills a critical gap for UWP developers experiencing Microsoft Store visual appearance issues, providing them with the knowledge and tools needed to resolve color display problems across different Store contexts.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Microsoft Store gradient color issue</issue_title>
<issue_description>I originally logged this as a support ticket with Microsoft but they told me Microsoft Store doesn't have developer support, so I have to log it here?

Anyway, we are having an issue with our Microsoft Store listing, in the web version of the store the gradient color is one color but the Microsoft Store app it is gray - we are setting it in our appxmanifest like so:

<uap:VisualElements
  DisplayName="Ingress"
  Description="Ingress"
  BackgroundColor="#0ab68e"
  Square150x150Logo="Assets\Square150x150Logo.png"
  Square44x44Logo="Assets\Square44x44Logo.png">
  <uap:DefaultTile Wide310x150Logo="Assets\Wide310x150Logo.png"  Square71x71Logo="Assets\SmallTile.png" Square310x310Logo="Assets\LargeTile.png" ShortName="Ingress">
    <uap:ShowNameOnTiles>
      <uap:ShowOn Tile="square150x150Logo"/>
      <uap:ShowOn Tile="square310x310Logo"/>
      <uap:ShowOn Tile="wide310x150Logo"/>
    </uap:ShowNameOnTiles>
  </uap:DefaultTile >
  <uap:SplashScreen Image="Assets\SplashScreen.png" BackgroundColor="#0ab68e"/>
</uap:VisualElements>

Any idea what we're doing wrong, or is there a bug with the store?

Here are some screenshots with the issues:

</issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes #5626

---

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[learn-build-service-prod]

Learn Build status updates of commit 76becd5:

⚠️ Validation status: warnings

For more details, please refer to the build report.

Note: Your PR may contain errors or warnings or suggestions unrelated to the files you changed. This happens when external dependencies like GitHub alias, Microsoft alias, cross repo links are updated. Please use these instructions to resolve them.

[learn-build-service-prod]

Learn Build status updates of commit 7fe2916:

⚠️ Validation status: warnings

File	Status	Preview URL	Details
uwp/launch-resume/microsoft-store-color-appearance-issues.md	⚠️Warning		Details
uwp/develop/toc.yml	✅Succeeded
uwp/launch-resume/add-a-splash-screen.md	✅Succeeded
uwp/launch-resume/splash-screens.md	✅Succeeded

uwp/launch-resume/microsoft-store-color-appearance-issues.md

• Line 115, Column 83: [Warning: link-out-of-scope - See documentation] File '../hub/apps/publish/publish-your-app/msix/screenshots-and-images.md' referenced by link '../../hub/apps/publish/publish-your-app/msix/screenshots-and-images.md' will not be built because it is not included in build scope.
• Line 140, Column 3: [Warning: link-out-of-scope - See documentation] File '../hub/apps/publish/publish-your-app/msix/screenshots-and-images.md' referenced by link '../../hub/apps/publish/publish-your-app/msix/screenshots-and-images.md' will not be built because it is not included in build scope.

For more details, please refer to the build report.

Note: Your PR may contain errors or warnings or suggestions unrelated to the files you changed. This happens when external dependencies like GitHub alias, Microsoft alias, cross repo links are updated. Please use these instructions to resolve them.

[learn-build-service-prod]

Learn Build status updates of commit 7e7925d:

⚠️ Validation status: warnings

File	Status	Preview URL	Details
uwp/launch-resume/microsoft-store-color-appearance-issues.md	⚠️Warning		Details
uwp/develop/toc.yml	✅Succeeded
uwp/launch-resume/add-a-splash-screen.md	✅Succeeded
uwp/launch-resume/splash-screens.md	✅Succeeded

uwp/launch-resume/microsoft-store-color-appearance-issues.md

• Line 117, Column 83: [Warning: link-out-of-scope - See documentation] File '../hub/apps/publish/publish-your-app/msix/screenshots-and-images.md' referenced by link '../../hub/apps/publish/publish-your-app/msix/screenshots-and-images.md' will not be built because it is not included in build scope.
• Line 142, Column 3: [Warning: link-out-of-scope - See documentation] File '../hub/apps/publish/publish-your-app/msix/screenshots-and-images.md' referenced by link '../../hub/apps/publish/publish-your-app/msix/screenshots-and-images.md' will not be built because it is not included in build scope.

For more details, please refer to the build report.

Note: Your PR may contain errors or warnings or suggestions unrelated to the files you changed. This happens when external dependencies like GitHub alias, Microsoft alias, cross repo links are updated. Please use these instructions to resolve them.

[GrantMeStrength]

Ipsita - Copilot suggested this topic to address a customer question. I am not qualified to review it. What do you think?