Flutter InAppWebView throwing error Uncaught (in promise) NotAllowedError: Write permission denied. when tested on Android devices

Question

Objective

• I am trying to copy a text from a copy button inside a web page. The copy function itself is working fine when i open it using chrome, firefox and safari browser

Expected behavior: After pressing the copy button, the text is copied into phone clipboard. Current behavior: After pressing the copy button, Flutter InAppWebView throwing error Uncaught (in promise) NotAllowedError: Write permission denied.

Step done to fix this error

1. I have added android permission inside my Project > android > app > src > main >AndroidManifest.xml

    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

2. PermissionRequestResponseAction is set to .GRANT, however, this callback is not called when i press on the copy button inside the web page

    androidOnPermissionRequest: (webViewController, origin, resources) async {
                      return PermissionRequestResponse(
                        resources: resources,
                        action: PermissionRequestResponseAction.GRANT,
                      );
                    },

3. javaScriptEnabled is set to true for Android, and its true by default

  InAppWebViewGroupOptions options = InAppWebViewGroupOptions(
      crossPlatform: InAppWebViewOptions(
          // allowFileAccessFromFileURLs: true,
          // javaScriptCanOpenWindowsAutomatically: true,
          // allowUniversalAccessFromFileURLs: true,
          javaScriptEnabled: true,
          useShouldOverrideUrlLoading: true,
          mediaPlaybackRequiresUserGesture: false),
      android: AndroidInAppWebViewOptions(
        useHybridComposition: true,
      ),
      ios: IOSInAppWebViewOptions(
        allowsInlineMediaPlayback: true,
      ));

Here are some related issue that have been asked, but still no solution for it:

1. webview_flutter: Uncaught (in promise) NotAllowedError: Write permission denied

2. https://github.com/pichillilorenzo/flutter_inappwebview/issues/678

How to solve for this error? Any help is much appreciated, thank you