21.08 PR: https://github.com/truenas/webui/pull/5663

12.0 PR: https://github.com/truenas/webui/pull/5659

It was deliberately hidden, but since we have the key in API response, there is no additional security benefit from not showing it.

I just tried FreeNAS 11.3U5 (still my prefered NAS) and I see I can reveal S3 secret key anytime. I like it! That is why I think that TrueNAS 12.0 has a bug that it doesn't show secret key.

I would like to highlight that security model in AWS is more complex. I can have several credentials (pair key/secret). When I forget "secret key", I cannot reveal it but I can define new credential (key+secret) and use it to configure new services. Client already connected to S3 are not affected and I have time to update configuration in other services. TrueNAS has only one credential pair, so when I change secret key, other services can be disconnected so I prefer to see configured "secret key".

The icon hide/show secret key works when I enter new secret key. But I cannot reveal the secret key later. I assumed this is a bug but this could be a design. I know that I cannot reveal most secrets in AWS but I do not require such high security from small NAS server... I preffer an option to reveal secret anyttime.