Amazon S3 protocol currently not supporting TLS/SSL Explicit encryption

Hello All,
The S3 endpoint which I am connecting required an client certificate to be passed.
In WinSCP version 6.3.3. it is not showing the option to upload the Client certificate file for the Amazon S3 protocol.
Currently "TLS/SSL Explicit encryption" and "Client certificate file" is showing only for FTP and WebDAV protocols only.
Is it possible to add the the option to upload the Client certificate file for the Amazon S3 protocol as well? Thank you

"TLS/SSL Explicit encryption" makes sense with FTP protocol only, not with S3 (nor with WebDAV). Why do you think you need it?

Client certificates are indeed not supported with S3 protocol – I've never heard of such requirement before. Anyway, I have added this request to the tracker:
Pending issues
You can vote for it there.