[TraitCollection] Class CKBrowserSwitcherViewController overrides the -traitCollection getter, which is not supported. If you\'re trying to override traits, you
You can ignore these messages as per iOS12 Beta 2 release notes:
When running your app from Xcode, you might see console errors about UIKit classes that override the traitCollection getter. You can safely ignore these messages for system classes. If you see this error message for your own classes, it likely indicates a real issue for you to fix. (51651561)
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