Support: Cannot login using certificate any more

Greetings,

When previously using WinSCP I was able to fill in the following details:
SFTP address
User name
.. and select a certificate before pressing Login to authenticate using the certificate.

I can no longer find the place to select the certificate, it appears to have disappeared from the login dialog.

Please can you help me.
Thanks in advance.

You have to click Advanced button and go to Authentication page of Advanced Site Settings dialog:
https://winscp.net/eng/docs/ui_login_authentication