音频记录按钮在WKWebView中不可见，但在Safari浏览器中可见

Question

我的应用程序中有一个WKWebview，它应该显示音频的录制按钮。但是，按钮本身不可见，并且会显示一些错误，但是在Safari浏览器中可以看到相同的按钮，并且该按钮也可以用于音频记录和播放。

func createWebView（）{

    let preferences = WKPreferences()
    preferences.javaScriptEnabled = true
    preferences.javaScriptCanOpenWindowsAutomatically = true
    preferences.setValue(true, forKey: "allowFileAccessFromFileURLs")

    let userContentController = WKUserContentController()
    userContentController.add(self, name: "observe")

    let configuration = WKWebViewConfiguration()
    configuration.preferences = preferences
    configuration.allowsAirPlayForMediaPlayback = true
    configuration.allowsInlineMediaPlayback = true
    configuration.allowsPictureInPictureMediaPlayback = true
    configuration.mediaTypesRequiringUserActionForPlayback = .audio

    configuration.userContentController = userContentController

    webView = WKWebView(frame: view.bounds, configuration: configuration)
    webView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
    webView.uiDelegate = self
    webView.navigationDelegate = self

    view.addSubview(webView)
}