XAML properties' default values

[weitzhandler]

Please include information about the default value of this property and in fact, all XAML properties' docs should include info about their default values.

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Document Details

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• ID: a4ebf3f8-f8c7-79aa-c4f8-831c7a4a9fab
• Version Independent ID: a4ebf3f8-f8c7-79aa-c4f8-831c7a4a9fab
• Content: TreeViewItem.IsExpanded Property (Microsoft.UI.Xaml.Controls) - Windows App SDK
• Content Source: winapps-winrt-build/xml/Microsoft.UI.Xaml.Controls/TreeViewItem.xml
• Service: windows-app-sdk
• Sub-service: reunion-reference
• GitHub Login: @jwmsft
• Microsoft Alias: jimwalk