 
 extension WKUserContentController {
     public func addInDefaultContentWorld(scriptMessageHandler: WKScriptMessageHandler, name: String) {
-        if #available(iOS 14.0, *), USE_NEW_SANDBOX_APIS {
+        if #available(iOS 14.3, *), USE_NEW_SANDBOX_APIS {
             add(scriptMessageHandler, contentWorld: .defaultClient, name: name)
         } else {
             add(scriptMessageHandler, name: name)

    ///     - javascript: String representing javascript to be evaluated
    public func evaluateJavascriptInDefaultContentWorld(_ javascript: String) {
        #if compiler(>=5.3)
            if #available(iOS 14.0, *), USE_NEW_SANDBOX_APIS {
                self.evaluateJavaScript(javascript, in: nil, in: .defaultClient, completionHandler: { _ in })
            } else {
                self.evaluateJavaScript(javascript)


extension WKUserScript {
    public class func createInDefaultContentWorld(source: String, injectionTime: WKUserScriptInjectionTime, forMainFrameOnly: Bool) -> WKUserScript {
        if #available(iOS 14.3, *), USE_NEW_SANDBOX_APIS {
            return WKUserScript(source: source, injectionTime: injectionTime, forMainFrameOnly: forMainFrameOnly, in: .defaultClient)
        } else {
            return WKUserScript(source: source, injectionTime: injectionTime, forMainFrameOnly: forMainFrameOnly)
