`ssh-keygen` does not generate ed25519 key with pem format

[Herbert J. Skuhra]

On Tue, 7 Jul 2026, at 08:57, Darren Rambaud via openssh-unix-dev wrote:
> Hi -- Using `10.3p1` release:
>
> ```
> # ssh -V
> OpenSSH_10.3p1, OpenSSL 3.6.2 7 Apr 2026
> ```
>
> I am trying to generate a public/private key pair with this command:
>
> ```
> ssh-keygen -f ./openssh103p1 -t ed25519 -N '' -m 'PEM'
> ```
>
> However, it fails to generate a public/private key pair due to:
>
> ```
> Generating public/private ed25519 key pair.
> Saving key "./openssh103p1" failed: invalid format
> ```

'git bisect' says:

2d0d26602f739b4a3ddde6c4dbc8f3ddab38ac0d is the first 'bad' commit

<https://github.com/openssh/openssh-portable/commit/2d0d26602f739b4a3ddde6c4dbc8f3ddab38ac0d>