Hi I have found the issue, it was a problem with my code, the return value should be a webview instead of a webkitwebview ??
in
UltimateWebView you return an UltimateWebView object, but in
WebKitLibrarySet you should pass a WebView
B4X:
Private Sub WKWebView1_CreateChildWindow (IsDialog As Boolean, IsUserGesture As Boolean) As WebView
and the return is made this way
B4X:
Return NewUltimateView.WebView