Worked on enhancing theming reliability in the CommunityToolkit/Maui repository by addressing a bug in AppThemeResource key lookup. Improved the logic for resource retrieval to ensure that resources could be accessed consistently from both page-level and application-level dictionaries, reducing the likelihood of theming errors in Maui applications. Utilized C# and XAML to refine the AppThemeResourceExtension, focusing on robust resource management practices. Added comprehensive unit tests to validate the new behavior and prevent future regressions. This work contributed to more stable releases by strengthening test coverage and ensuring that theming resources are reliably resolved across different scopes within the application.