The Web Browser widget doesn't use CEF on every platform. On some platforms the widget has to use the platform specific version, which prevents us from having total rendering control over it. Instead we allow the OS to render it in 2D above the airspace of the engine - but in the same 2D location of the widget.
Widget Component Web browser appears to be 2D when launching on to Android
Expected: The widget component would appear as it does in PIE
Result: The Widget component appears to become 2D
Head over to the existingAnswerHub thread and let us know what's up.