Add iOS option to lock portrait mode in browsing

iOS/AppDelegate.swift

@@ -0,0 +1,17 @@
+import Foundation
+import UIKit
+
+final class AppDelegate: UIResponder, UIApplicationDelegate {
+    var orientationLock = UIInterfaceOrientationMask.all
+
+    private(set) static var instance: AppDelegate!
+
+    func application(_: UIApplication, supportedInterfaceOrientationsFor _: UIWindow?) -> UIInterfaceOrientationMask {
+        orientationLock
+    }
+
+    func application(_: UIApplication, didFinishLaunchingWithOptions _: [UIApplication.LaunchOptionsKey: Any]? = nil) -> Bool { // swiftlint:disable:this discouraged_optional_collection
+        AppDelegate.instance = self
+        return true
+    }
+}