     }
 
     func apply(theme: Theme) {
-        for case let barButonItem as BarButtonItem in navigationItem.rightBarButtonItems ?? [] {
+        for case let barButonItem as BarButtonItem in navigationItem?.rightBarButtonItems ?? [] {
             barButonItem.apply(theme: theme)
         }
-        for case let barButonItem as BarButtonItem in navigationItem.leftBarButtonItems ?? [] {
+        for case let barButonItem as BarButtonItem in navigationItem?.leftBarButtonItems ?? [] {
             barButonItem.apply(theme: theme)
         }
     }

}

class SectionEditorNavigationItemController: NSObject, Themeable {
    private let navigationItem: UINavigationItem

    init(navigationItem: UINavigationItem) {
        self.navigationItem = navigationItem

        let closeButton = BarButtonItem(image: #imageLiteral(resourceName: "close"), style: .plain, target: self, action: #selector(close(_ :)), tintColorKeyPath: \Theme.colors.chromeText)
        closeButton.accessibilityLabel = CommonStrings.closeButtonAccessibilityLabel

        navigationItem?.leftBarButtonItem = closeButton

        navigationItem?.rightBarButtonItems = [
            progressButton,
            UIBarButtonItem.wmf_barButtonItem(ofFixedWidth: 20),
            separatorButton,
