Create RootSplitViewController in code rather than in storyboard.

NetNewsWire.xcodeproj/project.pbxproj

@@ -291,6 +291,7 @@
 		8498E53C2D27A766009F5438 /* PBXFileSystemSynchronizedBuildFileExceptionSet */ = {
 			isa = PBXFileSystemSynchronizedBuildFileExceptionSet;
 			membershipExceptions = (
+				/Localized/MainWindow/Main.storyboard,
 				/Localized/ShareExtension/MainInterface.storyboard,
 				IntentsExtension/Info.plist,
 				IntentsExtension/IntentHandler.swift,

iOS/AppDelegate.swift

@@ -82,12 +82,7 @@ final class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationC
 		self.window = window
 
 		// Create UI and add it to window.
-		let storyboard = UIStoryboard(name: "Main", bundle: nil)
+		let rootSplitViewController = RootSplitViewController()
-		let rootSplitViewController = storyboard.instantiateInitialViewController() as! RootSplitViewController
-		rootSplitViewController.presentsWithGesture = true
-		rootSplitViewController.showsSecondaryOnlyButton = true
-		rootSplitViewController.preferredDisplayMode = .oneBesideSecondary
-
 		coordinator = SceneCoordinator(rootSplitViewController: rootSplitViewController)
 		rootSplitViewController.coordinator = coordinator
 		rootSplitViewController.delegate = coordinator

iOS/MainWindow/RootSplitViewController.swift

@@ -11,7 +11,34 @@ import Account
 
 final class RootSplitViewController: UISplitViewController {
 
-	var coordinator: SceneCoordinator!
+	var coordinator: SceneCoordinator! {
+		didSet {
+			sidebarViewController.coordinator = coordinator
+			timelineViewController.coordinator = coordinator
+			articleViewController.coordinator = coordinator
+		}
+	}
+
+	private lazy var sidebarViewController = MainFeedViewController()
+	private lazy var timelineViewController = TimelineViewController()
+	private lazy var articleViewController = ArticleViewController()
+
+	init() {
+		super.init(style: .tripleColumn)
+
+		setViewController(self.sidebarViewController, for: .primary)
+		setViewController(self.timelineViewController, for: .supplementary)
+		setViewController(self.articleViewController, for: .secondary)
+
+		self.showsSecondaryOnlyButton = true
+		self.preferredDisplayMode = .oneBesideSecondary
+		self.preferredSplitBehavior = .displace
+		self.primaryBackgroundStyle = .sidebar
+	}
+
+	required init?(coder: NSCoder) {
+		fatalError("init(coder:) has not been implemented")
+	}
 	
 	override var prefersStatusBarHidden: Bool {
 		return coordinator.prefersStatusBarHidden