I am writing a UWP app that has a NavigationView containing NavigationViewItemHeaders:

Solution 1
Increase the left margin of item headers:
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Solution 2
Disable compact and expanded display mode of the NavigationView by setting the CompactModeThresholdWidth and ExpandedModeThresholdWidth to some big number:
Solution 3
Bind the Visibility property of item headers to the IsPaneOpen property of the NavigationView as André B suggested, only use x:Bind instead of Binding since it doesn't need a converter:
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