ok Andrea, adesso non ci sono errori e il codice completo che ho usato mischiando la prima parte della mia idea con la tua, è questo . . ma nella Label1 di controllo vedo solo il titolo della finestra del browser e non l'indirizzo . . perchè l'urlHandle resta sempre = 0
Questo 'Chrome_AutocompleteEditView' . . .è proprio quello che dobbiamo cercare?

codice:
Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal Msg As Long, wParam As Any, lParam As Any) As Long
Private Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Long, ByVal hWnd2 As Long, ByVal lpsz1 As String, ByVal lpsz2 As String) As Long
Private Declare Function GetWindowText Lib "user32" Alias "GetWindowTextA" (ByVal hwnd As Long, ByVal lpString As String, ByVal cch As Long) As Long
Private Declare Function GetWindowTextLength Lib "user32" Alias "GetWindowTextLengthA" (ByVal hwnd As Long) As Long
Private Declare Function GetForegroundWindow Lib "user32" () As Long

Private Const WM_GETTEXTLENGTH As Integer = &HE
Private Const WM_GETTEXT As Integer = &HD

Dim title As String
Dim handle As Long, length As Long

Private Sub Timer1_Timer() 
    '  intervallo impostato nelle proprietà a 300 millisecondi
    handle = GetForegroundWindow
    length = GetWindowTextLength(handle)
    title = String(length, Chr$(0))
    GetWindowText handle, title, length + 1
    If InStr(title, "Google Chrome") > 0 Then Label1 = title + ">>" + getChromeUrl(handle)
End Sub

Public Function getChromeUrl(winHandle As Long) As String
    Const nChars As Integer = 256
    Dim browserUrl As String
    Dim urlHandle As Integer
    Dim b As String
    Dim length As Integer
    browserUrl = ""
    length = SendMessage(urlHandle, WM_GETTEXTLENGTH, 0, 0)
    urlHandle = FindWindowEx(winHandle, 0, "Chrome_AutocompleteEditView", "")
    
   '  l' urlHandle non trova mai nulla <<<<<<<<<<<<<<<<<<<<<<

    If length > 0 Then
        b = String(nChars, " ")
        SendMessage urlHandle, WM_GETTEXT, nChars, b
        browserUrl = b
    End If
    getChromeUrl = browserUrl
End Function