Can I disable duplicate public key check from dropbear client?

[M Rubon]

When I use dropbear client, it causes a duplicate public key check on
the openssh server.  Is there any way of preventing this separate
[preauth] check from happening?    For my application it is very
useful to have the authentication attempted just once.

A StackExchange comment (dave_thompson_085 on
https://superuser.com/q/1116927 ) to a different SSH question notes
that
> The [preauth] on those log lines and the Postponed result (both) mean
> the client sent authreq with method=publickey and boolean=FALSE to "query"
> whether the pubkey "would be acceptable" (see rfc4252 section 7).

This matches what I see in the OpenSSH logs below.

I checked and do not see this [preauth] when I do the same connection
from an OpenSSH client.

Mike


I am connecting from my router using dropbear.   The command I use is
    ssh -i .ssh/id_rsa  fast at cat

On the OpenSSH server I see:
Feb 19 15:41:09 cat sshd[17906]: Accepted key RSA
SHA256:iJN19jufdHFey0pwLK70PqgV3rgT99iQaWVmY7M8qZ0 found at
/home/fast/.ssh/authorized_keys:16
Feb 19 15:41:09 cat sshd[17906]: Postponed publickey for fast from
45.78.113.202 port 48930 ssh2 [preauth]
Feb 19 15:41:09 cat sshd[17906]: Accepted key RSA
SHA256:iJN19jufdHFey0pwLK70PqgV3rgT99iQaWVmY7M8qZ0 found at
/home/fast/.ssh/authorized_keys:16
Feb 19 15:41:09 cat sshd[17906]: Accepted publickey for fast from
45.78.113.202 port 48930 ssh2: RSA
SHA256:iJN19jufdHFey0pwLK70PqgV3rgT99iQaWVmY7M8qZ0
Feb 19 15:41:09 cat sshd[17906]: pam_unix(sshd:session): session
opened for user fast by (uid=0)