Hmmm, default User-Agent strings for Debian chromium and midori: Mozilla/5.0 (X11; Linux i686) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2490.71 Safari/537.36 Mozilla/5.0 (X11; Linux) AppleWebKit/538.15 (KHTML, like Gecko) Chrome/18.0.1025.133 Safari/538.15 Midori/0.5
So it seems that while Midori keeps its AppleWebKit and Safari version numbers ahead of chromium, for some reason its Chrome number got stuck long ago, until finally trigger this Google warning. And there in fact is a Midori string at back there, so maybe it is not entirely impersonating, its just that its Chrome version got stuck at 18.
