X ssh forwarding not working from a macOS 13.4.1 to Debian Linux 11

I have currently an issue about trying to get a SSH X forwarding connection from a macOS Ventura to a Debian Linux 11. I am using XQuartz 2.8.4 (2.8.5 failed in installation). I don't know where the problem comes from. Below a lot of informations with -vvv option : ssh -X -vvv fab@pablo OpenSSH_9.0p1, LibreSSL 3.3.6 debug1: Reading configuration data /etc/ssh/ssh_config debug1: /etc/ssh/ssh_config line 21: include /etc/ssh/ssh_config.d/* matched no files debug1: /etc/ssh/ssh_config line 54: Applying options for * debug1: /etc/ssh/ssh_config line 58: Applying options for * debug3: expanded UserKnownHostsFile '~/.ssh/known_hosts' -> '/Users/fab/.ssh/known_hosts' debug3: expanded UserKnownHostsFile '~/.ssh/known_hosts2' -> '/Users/fab/.ssh/known_hosts2' debug1: Authenticator provider $SSH_SK_PROVIDER did not resolve; disabling debug1: Connecting to pablo port 22. debug1: Connection established. debug1: identity file /Users/fab/.ssh/id_rsa type -1 debug1: identity file /Users/fab/.ssh/id_rsa-cert type -1 debug1: identity file /Users/fab/.ssh/id_ecdsa type -1 debug1: identity file /Users/fab/.ssh/id_ecdsa-cert type -1 debug1: identity file /Users/fab/.ssh/id_ecdsa_sk type -1 debug1: identity file /Users/fab/.ssh/id_ecdsa_sk-cert type -1 debug1: identity file /Users/fab/.ssh/id_ed25519 type -1 debug1: identity file /Users/fab/.ssh/id_ed25519-cert type -1 debug1: identity file /Users/fab/.ssh/id_ed25519_sk type -1 debug1: identity file /Users/fab/.ssh/id_ed25519_sk-cert type -1 debug1: identity file /Users/fab/.ssh/id_xmss type -1 debug1: identity file /Users/fab/.ssh/id_xmss-cert type -1 debug1: identity file /Users/fab/.ssh/id_dsa type -1 debug1: identity file /Users/fab/.ssh/id_dsa-cert type -1 debug1: Local version string SSH-2.0-OpenSSH_9.0 debug1: Remote protocol version 2.0, remote software version OpenSSH_8.4p1 Debian-5+deb11u1 debug1: compat_banner: match: OpenSSH_8.4p1 Debian-5+deb11u1 pat OpenSSH* compat 0x04000000 debug3: fd 5 is O_NONBLOCK debug1: Authenticating to pablo:22 as 'fab' debug3: record_hostkey: found key type ED25519 in file /Users/fab/.ssh/known_hosts:1 debug3: record_hostkey: found key type ECDSA in file /Users/fab/.ssh/known_hosts:2 debug3: load_hostkeys_file: loaded 2 keys from pablo debug1: load_hostkeys: fopen /Users/fab/.ssh/known_hosts2: No such file or directory debug1: load_hostkeys: fopen /etc/ssh/ssh_known_hosts: No such file or directory debug1: load_hostkeys: fopen /etc/ssh/ssh_known_hosts2: No such file or directory debug3: order_hostkeyalgs: have matching best-preference key type ssh-ed25519-cert-v01@openssh.com, using HostkeyAlgorithms verbatim debug3: send packet: type 20 debug1: SSH2_MSG_KEXINIT sent debug3: receive packet: type 20 debug1: SSH2_MSG_KEXINIT received debug2: local client KEXINIT proposal debug2: KEX algorithms: sntrup761x25519-sha512@openssh.com,curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group14-sha256,ext-info-c debug2: host key algorithms: ssh-ed25519-cert-v01@openssh.com,ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,rsa-sha2-512-cert-v01@openssh.com,rsa-sha2-256-cert-v01@openssh.com,ssh-ed25519,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,rsa-sha2-512,rsa-sha2-256 debug2: ciphers ctos: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com debug2: ciphers stoc: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com debug2: MACs ctos: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1 debug2: MACs stoc: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1 debug2: compression ctos: none,zlib@openssh.com,zlib debug2: compression stoc: none,zlib@openssh.com,zlib debug2: languages ctos: debug2: languages stoc: debug2: first_kex_follows 0 debug2: reserved 0 debug2: peer server KEXINIT proposal debug2: KEX algorithms: curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group14-sha256 debug2: host key algorithms: rsa-sha2-512,rsa-sha2-256,ssh-rsa,ecdsa-sha2-nistp256,ssh-ed25519 debug2: ciphers ctos: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com debug2: ciphers stoc: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com debug2: MACs ctos: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1 debug2: MACs stoc: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1 debug2: compression ctos: none,zlib@openssh.com debug2: compression stoc: none,zlib@openssh.com debug2: languages ctos: debug2: languages stoc: debug2: first_kex_follows 0 debug2: reserved 0 debug1: kex: algorithm: curve25519-sha256 debug1: kex: host key algorithm: ssh-ed25519 debug1: kex: server->client cipher: chacha20-poly1305@openssh.com MAC: compression: none debug1: kex: client->server cipher: chacha20-poly1305@openssh.com MAC: compression: none debug3: send packet: type 30 debug1: expecting SSH2_MSG_KEX_ECDH_REPLY debug3: receive packet: type 31 debug1: SSH2_MSG_KEX_ECDH_REPLY received debug1: Server host key: ssh-ed25519 SHA256:GLFoF6k2v/2MxuWrF1yK62AkZHsxKjH15LdXOC8PNIY debug3: record_hostkey: found key type ED25519 in file /Users/fab/.ssh/known_hosts:1 debug3: record_hostkey: found key type ECDSA in file /Users/fab/.ssh/known_hosts:2 debug3: load_hostkeys_file: loaded 2 keys from pablo debug1: load_hostkeys: fopen /Users/fab/.ssh/known_hosts2: No such file or directory debug1: load_hostkeys: fopen /etc/ssh/ssh_known_hosts: No such file or directory debug1: load_hostkeys: fopen /etc/ssh/ssh_known_hosts2: No such file or directory debug1: Host 'pablo' is known and matches the ED25519 host key. debug1: Found key in /Users/fab/.ssh/known_hosts:1 debug3: send packet: type 21 debug2: ssh_set_newkeys: mode 1 debug1: rekey out after 134217728 blocks debug1: SSH2_MSG_NEWKEYS sent debug1: expecting SSH2_MSG_NEWKEYS debug3: receive packet: type 21 debug1: SSH2_MSG_NEWKEYS received debug2: ssh_set_newkeys: mode 0 debug1: rekey in after 134217728 blocks debug1: get_agent_identities: bound agent to hostkey debug1: get_agent_identities: ssh_fetch_identitylist: agent contains no identities debug1: Will attempt key: /Users/fab/.ssh/id_rsa debug1: Will attempt key: /Users/fab/.ssh/id_ecdsa debug1: Will attempt key: /Users/fab/.ssh/id_ecdsa_sk debug1: Will attempt key: /Users/fab/.ssh/id_ed25519 debug1: Will attempt key: /Users/fab/.ssh/id_ed25519_sk debug1: Will attempt key: /Users/fab/.ssh/id_xmss debug1: Will attempt key: /Users/fab/.ssh/id_dsa debug2: pubkey_prepare: done debug3: send packet: type 5 debug3: receive packet: type 7 debug1: SSH2_MSG_EXT_INFO received debug1: kex_input_ext_info: server-sig-algs= debug3: receive packet: type 6 debug2: service_accept: ssh-userauth debug1: SSH2_MSG_SERVICE_ACCEPT received debug3: send packet: type 50 debug3: receive packet: type 51 debug1: Authentications that can continue: publickey,password debug3: start over, passed a different list publickey,password debug3: preferred publickey,keyboard-interactive,password debug3: authmethod_lookup publickey debug3: remaining preferred: keyboard-interactive,password debug3: authmethod_is_enabled publickey debug1: Next authentication method: publickey debug1: Trying private key: /Users/fab/.ssh/id_rsa debug3: no such identity: /Users/fab/.ssh/id_rsa: No such file or directory debug1: Trying private key: /Users/fab/.ssh/id_ecdsa debug3: no such identity: /Users/fab/.ssh/id_ecdsa: No such file or directory debug1: Trying private key: /Users/fab/.ssh/id_ecdsa_sk debug3: no such identity: /Users/fab/.ssh/id_ecdsa_sk: No such file or directory debug1: Trying private key: /Users/fab/.ssh/id_ed25519 debug3: no such identity: /Users/fab/.ssh/id_ed25519: No such file or directory debug1: Trying private key: /Users/fab/.ssh/id_ed25519_sk debug3: no such identity: /Users/fab/.ssh/id_ed25519_sk: No such file or directory debug1: Trying private key: /Users/fab/.ssh/id_xmss debug3: no such identity: /Users/fab/.ssh/id_xmss: No such file or directory debug1: Trying private key: /Users/fab/.ssh/id_dsa debug3: no such identity: /Users/fab/.ssh/id_dsa: No such file or directory debug2: we did not send a packet, disable method debug3: authmethod_lookup password debug3: remaining preferred: ,password debug3: authmethod_is_enabled password debug1: Next authentication method: password fab@pablo's password: debug3: send packet: type 50 debug2: we sent a password packet, wait for reply debug3: receive packet: type 52 Authenticated to pablo ([192.168.1.62]:22) using "password". debug1: channel 0: new [client-session] debug3: ssh_session2_open: channel_new: 0 debug2: channel 0: send open debug3: send packet: type 90 debug1: Requesting no-more-sessions@openssh.com debug3: send packet: type 80 debug1: Entering interactive session. debug1: pledge: exec debug3: receive packet: type 80 debug1: client_input_global_request: rtype hostkeys-00@openssh.com want_reply 0 debug3: client_input_hostkeys: received RSA key SHA256:/qSKL8wq3JtHIJiXzu+62UH3nbjm+fObXjBofpoqPyo debug3: client_input_hostkeys: received ECDSA key SHA256:76LnGQ12/LisJhH5vvrWgCdn2I/oxOzhcuLnO9+6LYQ debug3: client_input_hostkeys: received ED25519 key SHA256:GLFoF6k2v/2MxuWrF1yK62AkZHsxKjH15LdXOC8PNIY debug1: client_input_hostkeys: searching /Users/fab/.ssh/known_hosts for pablo / (none) debug3: hostkeys_foreach: reading file "/Users/fab/.ssh/known_hosts" debug3: hostkeys_find: found ssh-ed25519 key at /Users/fab/.ssh/known_hosts:1 debug3: hostkeys_find: found ecdsa-sha2-nistp256 key at /Users/fab/.ssh/known_hosts:2 debug1: client_input_hostkeys: searching /Users/fab/.ssh/known_hosts2 for pablo / (none) debug1: client_input_hostkeys: hostkeys file /Users/fab/.ssh/known_hosts2 does not exist debug3: client_input_hostkeys: 3 server keys: 1 new, 1 retained, 1 incomplete match. 0 to remove debug3: client_input_hostkeys: asking server to prove ownership for 1 keys debug3: send packet: type 80 debug3: receive packet: type 91 debug2: channel_input_open_confirmation: channel 0: callback start debug2: client_x11_get_proto: xauth command: /opt/X11/bin/xauth -f /var/folders/1n/6wz8wzkn63n8y1zc2xjcm6640000gn/T//ssh-Tw35M0laihwY/xauthfile generate /private/tmp/com.apple.launchd.qpHhyhgMf3/org.xquartz:0 MIT-MAGIC-COOKIE-1 untrusted timeout 1260 2>/dev/null It seems that XQuartz doesn't open the X after typing the password, I don't understand. If someone has already got this type of issue or sees its cause, I am lost with these many log informations ... **UPDATE 1 :** Here an example (where I have deleted the known_hosts on both side) : $ ssh -Y fab@pablo The authenticity of host 'pablo (192.168.1.62)' can't be established. ED25519 key fingerprint is SHA256:GLFoF6k2v/2MxuWrF1yK62AkZHsxKjH15LdXOC8PNIY. This key is not known by any other names Are you sure you want to continue connecting (yes/no/[fingerprint])? yes Warning: Permanently added 'pablo' (ED25519) to the list of known hosts. fab@pablo's password: Linux pablo 5.10.0-23-amd64 #1 SMP Debian 5.10.179-2 (2023-07-14) x86_64 The programs included with the Debian GNU/Linux system are free software; the exact distribution terms for each program are described in the individual files in /usr/share/doc/*/copyright. Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent permitted by applicable law. Last login: Wed Aug 2 01:17:43 2023 from 192.168.1.66 and doesn't display the rest. **UPDATE 2 :** I keep on my investigations about my issue. I found out that if I set on remote the environment variable to DISPLAY=localhost:10.0, then the X of server is working ( after a ssh -Y fab@pablo ) : I mean, I can launch for example nedit from remote machine and the window will appear on my macOS Ventura. I realized there is a code snippet into the ~/.zshrc of current user on remote machine : ############ FOR X11 Fowarding ############## if [ -e "$DISPLAY" ]; then DISPDIR=$(dirname $DISPLAY) NEWDISP="${DISPDIR}/:0" if [ ! -e "$NEWDISP" ]; then ln -s "$DISPLAY" "$NEWDISP" xauth -q generate "$NEWDISP" . fi export DISPLAY="$NEWDISP" fi but I don't remember what this part does exactly. Ideally, I would like that ssh connextion puts automatically the right value for variable DISPLAY : either directly on the machine (127.0.0.1:0.0) and from the macOS (127.0.0.1:10) when I do a ssh -X fab@pablo.