[ubu 18.04] Thunar1.6.15 won't browse remote samba shares

After upgrading to the ubuntu 18.04 I canno't browse my remote network shares. It was perfectly working in 17.10 until now. I'm not exactly sure that the Thunar is guilty.

If i try to browse the 'Windows network' in Thunar I get this
May 13 19:13:27 chrome org.gtk.vfs.Daemon[974]: Kerberos auth with 'user@WORKGROUP' (WORKGROUP\user) to access '192.168.1.1' not possible

If I mount the share manually using 'gvfs-mount -a smb://192.168.1.1/media' it is mounted without any warning or error and then Thunar is able to browse mounted share

What is it about?

PS: I tried to file a bug here on launchpad from the xfce-project page but it only allows to file bugs for the xfce4-volumed project (sic!)