NSOpenPanel Swift warning message on OSX 10.12

Question

Recently updated to macOS Sierra version 10.12, version Xcode 8.2.1

The following code works on OS Sierra, but with a warning message. It runs on previous OS EI Capitan 10.11 without warning.

Can anyone advise how to get a message about this warning?

warning: <NSRemoteView: 0x618000123200> determined it was necessary to configure <NSVBOpenPanel: 0x102e816d0> to support remote view vibrancy

my code is below:

@IBAction func btnChooseFile(_ sender: Any)
    {
        let dialog = NSOpenPanel()
        dialog.title                   = "Choose a project file"
        dialog.showsResizeIndicator    = true
        dialog.showsHiddenFiles        = false
        dialog.canChooseDirectories    = false
        dialog.canCreateDirectories    = false
        dialog.allowsMultipleSelection = false
        dialog.allowedFileTypes        = ["txt"]

        if (dialog.runModal() == NSModalResponseOK) {
            let result = dialog.url // Pathname of the file
            if (result != nil) {
                let path = result!.path
                txtProject.stringValue = path
            }else{
                // Display error message
            }
        } else {
            return
        }
    }