Pobieranie w tle

 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        WebBrowser1.Document.GetElementById("youtube-url").SetAttribute("value", TextBox1.Text)
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        WebBrowser1.Document.GetElementById("submit").InvokeMember("click")
    End Sub

    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
        Try
retry:
            Application.DoEvents()
            WebBrowser1.Document.GetElementById("youtube-url").SetAttribute("value", TextBox1.Text)
            WebBrowser1.Document.GetElementById("submit").InvokeMember("click")
            Dim dl_link As HtmlElement = WebBrowser1.Document.GetElementById("dl_link")
            Dim link As HtmlElementCollection = dl_link.GetElementsByTagName("a")
            Dim url As String = link(2).GetAttribute("href")
            WebBrowser1.Navigate(url)
        Catch ex As Exception
            GoTo retry
        End Try
    End Sub

    Private Sub WebBrowser1_Navigated(ByVal sender As Object, ByVal e As System.Windows.Forms.WebBrowserNavigatedEventArgs) Handles WebBrowser1.Navigated
        Button1.Enabled = True
        Button2.Enabled = True
        Button3.Enabled = True
        Label2.Visible = False
    End Sub

    Private Sub WebBrowser1_Navigating(ByVal sender As Object, ByVal e As System.Windows.Forms.WebBrowserNavigatingEventArgs) Handles WebBrowser1.Navigating
        Button1.Enabled = False
        Button2.Enabled = False
        Button3.Enabled = False
        Label2.Visible = True
    End Sub

Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
        Dim zapisz As New FolderBrowserDialog
        zapisz.ShowDialog()
        TextBox2.Text = zapisz.SelectedPath
    End Sub