incompatibility bug with OpenSSH-6.9p1 generated keys and Chrome Secure Shell hterm/ssh extension

raw term output

debug1: Connection established.
debug1: identity file /.ssh/demonstration-key type 1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.6
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.7
debug1: match: OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.7 pat OpenSSH* compat 0x04000000
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr [email protected] [email protected]
debug1: kex: client->server aes128-ctr [email protected] [email protected]
debug1: sending SSH2_MSG_KEX_ECDH_INIT
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ECDSA d3:10:fc:04:90:15:07:4c:cf:9c:05:29:87:85:c2:2d
debug1: Host '0.example.com' is known and matches the ECDSA host key.
debug1: Found key in /.ssh/known_hosts:6
debug1: ssh_ecdsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /.ssh/demonstration-key
debug1: Server accepts key: pkalg ssh-rsa blen 279
debug1: key_parse_private2: missing begin marker
debug1: key_parse_private_pem: PEM_read_PrivateKey failed
debug1: read PEM private key done: type <unknown>
Enter passphrase for key '/.ssh/demonstration-key':