Tunneling through SSH-1 connection

Session to tunnel through SSH-1 connection is disabled after version 5.15.9.
I use some settings sessions to tunnel through SSH connection using WinSCP 5.15.9.
When I update to WinSCP 5.16 after (any version),
tunnel through SSH-2 is available but tunnel through SSH-1 is failed to authentication.
When I re-install WinSCP 5.15.9. then tunnel through SSH-1 is available again.

Is it tunneling problem only? Or do plain direct SSH-1 connections fail as well? Please post session log files from both versions.