Comment # 7 on bug 949808 from Andrei Borzenkov

(In reply to Stefan Seyfried from comment #6)
> ping, does the package
> http://download.opensuse.org/repositories/home:/seife:/xfce/
> openSUSE_Tumbleweed/x86_64/ (thunar-volman-0.8.1-42.1.x86_64.rpm right now)
> fix the issue for you?

Yes, device is not mounted automatically (install thunar and thunar-volume);
tested under Leap 42.3 (which is what I have with XFCE right now).