Firefox Browser extensions fails FIDO2 Extension 2026.8.0

[PureOxygen-Dev]

Prerequisites

• I have searched the existing Closed AND Open Issues AND Discussions
• I have searched and read the documentation

Vaultwarden Support String

Your environment (Generated via diagnostics page)

• Vaultwarden version: v1.37.2
• Web-vault version: v2026.7.0
• OS/Arch: linux/x86_64
• Running within a container: yes ➕ (Base: Debian)
• Database type: SQLite
• Database version: 3.51.3
• Uses config.json: no ➖
• Uses custom templates: no ➖
• Uses a reverse proxy: no ➖
• Internet access: true ✅
• Internet access via a proxy: no ➖
• DNS Check: true ✅
• Browser/Server Time Check: true ✅
• Server/NTP Time Check: true ✅
• Domain Configuration Check: false ❌
• HTTPS Check: true ✅
• Websocket Check: true ✅
• HTTP Response Checks: true ✅

Config & Details (Generated via diagnostics page)

Show Config & Details

Config:

{
  "data_folder": "data",
  "database_url": "******://***************",
  "icon_cache_folder": "data/icon_cache",
  "attachments_folder": "data/attachments",
  "sends_folder": "data/sends",
  "tmp_folder": "data/tmp",
  "templates_folder": "data/templates",
  "rsa_key_filename": "data/rsa_key",
  "web_vault_folder": "web-vault/",
  "enable_websocket": true,
  "push_enabled": false,
  "push_relay_uri": "https://push.bitwarden.com",
  "push_identity_uri": "https://identity.bitwarden.com",
  "push_installation_id": "***",
  "push_installation_key": "***",
  "job_poll_interval_ms": 30000,
  "send_purge_schedule": "0 5 * * * *",
  "trash_purge_schedule": "0 5 0 * * *",
  "incomplete_2fa_schedule": "30 * * * * *",
  "emergency_notification_reminder_schedule": "0 3 * * * *",
  "emergency_request_timeout_schedule": "0 7 * * * *",
  "event_cleanup_schedule": "0 10 0 * * *",
  "auth_request_purge_schedule": "30 * * * * *",
  "duo_context_purge_schedule": "30 * * * * *",
  "purge_incomplete_sso_auth": "0 20 0 * * *",
  "domain": "*****://********************",
  "domain_set": true,
  "domain_origin": "*****://********************",
  "domain_path": "",
  "web_vault_enabled": true,
  "sends_allowed": true,
  "hibp_api_key": null,
  "user_attachment_limit": null,
  "org_attachment_limit": null,
  "user_send_limit": null,
  "trash_auto_delete_days": null,
  "incomplete_2fa_time_limit": 3,
  "disable_icon_download": false,
  "signups_allowed": false,
  "signups_verify": false,
  "signups_verify_resend_time": 3600,
  "signups_verify_resend_limit": 6,
  "signups_domains_whitelist": "",
  "org_events_enabled": false,
  "org_creation_users": "",
  "invitations_allowed": false,
  "invitation_expiration_hours": 120,
  "emergency_access_allowed": true,
  "email_change_allowed": true,
  "password_iterations": 600000,
  "password_hints_allowed": true,
  "show_password_hint": false,
  "admin_token": "***",
  "invitation_org_name": "Vaultwarden",
  "events_days_retain": null,
  "client_suppress_onboarding": false,
  "ip_header": "X-Real-IP",
  "_ip_header_enabled": true,
  "ip_header_trusted_proxies": "local",
  "icon_service": "internal",
  "_icon_service_url": "",
  "_icon_service_csp": "",
  "icon_redirect_code": 302,
  "icon_cache_ttl": 2592000,
  "icon_cache_negttl": 259200,
  "icon_download_timeout": 10,
  "icon_blacklist_regex": null,
  "icon_blacklist_non_global_ips": true,
  "http_request_block_regex": null,
  "http_request_block_non_global_ips": true,
  "disable_2fa_remember": false,
  "authenticator_disable_time_drift": false,
  "experimental_client_feature_flags": "",
  "require_device_email": false,
  "reload_templates": false,
  "extended_logging": true,
  "log_timestamp_format": "%Y-%m-%d %H:%M:%S.%3f",
  "use_syslog": false,
  "log_file": null,
  "log_level": "info",
  "enable_db_wal": true,
  "db_connection_retries": 15,
  "database_timeout": 30,
  "database_idle_timeout": 600,
  "database_max_conns": 10,
  "database_min_conns": 2,
  "database_conn_init": "",
  "disable_admin_token": false,
  "allowed_iframe_ancestors": "",
  "allowed_connect_src": "",
  "login_ratelimit_seconds": 60,
  "login_ratelimit_max_burst": 10,
  "unauthenticated_ratelimit_seconds": 60,
  "unauthenticated_ratelimit_max_burst": 50,
  "admin_ratelimit_seconds": 300,
  "admin_ratelimit_max_burst": 3,
  "admin_session_lifetime": 20,
  "org_groups_enabled": false,
  "increase_note_size_limit": false,
  "_max_note_size": 10000,
  "enforce_single_org_with_reset_pw_policy": false,
  "dns_prefer_ipv6": false,
  "sso_enabled": false,
  "sso_only": false,
  "sso_signups_match_email": true,
  "sso_allow_unknown_email_verification": false,
  "sso_client_id": "",
  "sso_client_secret": "***",
  "sso_authority": "",
  "sso_scopes": "email profile",
  "sso_authorize_extra_params": "",
  "sso_pkce": true,
  "sso_audience_trusted": null,
  "sso_callback_path": "*****://*************************************************",
  "sso_master_password_policy": null,
  "sso_auth_only_not_session": false,
  "sso_client_cache_expiration": 0,
  "sso_debug_tokens": false,
  "_enable_yubico": false,
  "yubico_client_id": null,
  "yubico_secret_key": null,
  "yubico_server": null,
  "_enable_duo": false,
  "duo_use_iframe": false,
  "duo_ikey": null,
  "duo_skey": null,
  "duo_host": null,
  "_duo_akey": null,
  "_enable_smtp": true,
  "use_sendmail": false,
  "sendmail_command": null,
  "smtp_host": "*******************",
  "smtp_ssl": null,
  "smtp_explicit_tls": null,
  "smtp_security": "starttls",
  "smtp_port": 587,
  "smtp_from": "**************************",
  "smtp_from_name": "*****************",
  "smtp_username": "********************",
  "smtp_password": "***",
  "smtp_auth_mechanism": null,
  "smtp_timeout": 15,
  "helo_name": null,
  "smtp_embed_images": true,
  "_smtp_img_src": "***:",
  "smtp_debug": false,
  "smtp_accept_invalid_certs": false,
  "smtp_accept_invalid_hostnames": false,
  "_enable_email_2fa": false,
  "email_token_size": 6,
  "email_expiration_time": 600,
  "email_attempts_limit": 3,
  "email_2fa_enforce_on_verified_invite": false,
  "email_2fa_auto_fallback": false
}

Vaultwarden Build Version

1.37.2

Deployment method

Official Container Image

Custom deployment method

No response

Reverse Proxy

Ngnix Proxy Manager

Host/Server Operating System

Linux

Operating System Version

Alpine 3.24.1

Clients

Browser Extension

Client Version

Firefox 2026.8.0

Steps To Reproduce

1. Goto Extension
2. Enter email address
3. Enter Master Password
4. Click Open Browser
5. Handle Fido2 Auth
6. Error displayed

Expected Result

Should logon after key is presented.

Actual Result

Does not logon and if attempting again states invalid Master Password.

Logs

Nothing obvious

Screenshots or Videos

No response

Additional Context

Rolling back to FF Extension 2026.7 .0 works fine as expected.

[masterjg]

Yeah, yubikey does not allow to login anymore too. Extension tells that it's invalid key.

[BlackDex]

Your domain config seems to be invalid. This could have impact on your keys since those are linked to a specific domain to prevent mitm and stolen database details.

If you have recently changed your domain, that might be an issue.
But i have tested this multiple times now already and it works fine.

[PureOxygen-Dev]

Hi @BlackDex, the domain mismatch is only for the /Admin I do not publish that to the internet so reach the VaultWarden /admin using the IP and port so you get the mismatch thrown. For the rest the match is perfect.

Here I opened it to demonstrate

Your environment (Generated via diagnostics page)

• Vaultwarden version: v1.37.2
• Web-vault version: v2026.7.0
• OS/Arch: linux/x86_64
• Running within a container: yes ➕ (Base: Debian)
• Database type: SQLite
• Database version: 3.51.3
• Uses config.json: no ➖
• Uses custom templates: no ➖
• Uses a reverse proxy: yes ➕
• IP Header check: true ✅ (X-Real-IP)
• Internet access: true ✅
• Internet access via a proxy: no ➖
• DNS Check: true ✅
• Browser/Server Time Check: true ✅
• Server/NTP Time Check: true ✅
• Domain Configuration Check: true ✅
• HTTPS Check: true ✅
• Websocket Check: true ✅
• HTTP Response Checks: true ✅

Config & Details (Generated via diagnostics page)

Show Config & Details

Config:

{
  "data_folder": "data",
  "database_url": "******://***************",
  "icon_cache_folder": "data/icon_cache",
  "attachments_folder": "data/attachments",
  "sends_folder": "data/sends",
  "tmp_folder": "data/tmp",
  "templates_folder": "data/templates",
  "rsa_key_filename": "data/rsa_key",
  "web_vault_folder": "web-vault/",
  "enable_websocket": true,
  "push_enabled": false,
  "push_relay_uri": "https://push.bitwarden.com",
  "push_identity_uri": "https://identity.bitwarden.com",
  "push_installation_id": "***",
  "push_installation_key": "***",
  "job_poll_interval_ms": 30000,
  "send_purge_schedule": "0 5 * * * *",
  "trash_purge_schedule": "0 5 0 * * *",
  "incomplete_2fa_schedule": "30 * * * * *",
  "emergency_notification_reminder_schedule": "0 3 * * * *",
  "emergency_request_timeout_schedule": "0 7 * * * *",
  "event_cleanup_schedule": "0 10 0 * * *",
  "auth_request_purge_schedule": "30 * * * * *",
  "duo_context_purge_schedule": "30 * * * * *",
  "purge_incomplete_sso_auth": "0 20 0 * * *",
  "domain": "*****://********************",
  "domain_set": true,
  "domain_origin": "*****://********************",
  "domain_path": "",
  "web_vault_enabled": true,
  "sends_allowed": true,
  "hibp_api_key": null,
  "user_attachment_limit": null,
  "org_attachment_limit": null,
  "user_send_limit": null,
  "trash_auto_delete_days": null,
  "incomplete_2fa_time_limit": 3,
  "disable_icon_download": false,
  "signups_allowed": false,
  "signups_verify": false,
  "signups_verify_resend_time": 3600,
  "signups_verify_resend_limit": 6,
  "signups_domains_whitelist": "",
  "org_events_enabled": false,
  "org_creation_users": "",
  "invitations_allowed": false,
  "invitation_expiration_hours": 120,
  "emergency_access_allowed": true,
  "email_change_allowed": true,
  "password_iterations": 600000,
  "password_hints_allowed": true,
  "show_password_hint": false,
  "admin_token": "***",
  "invitation_org_name": "Vaultwarden",
  "events_days_retain": null,
  "client_suppress_onboarding": false,
  "ip_header": "X-Real-IP",
  "_ip_header_enabled": true,
  "ip_header_trusted_proxies": "local",
  "icon_service": "internal",
  "_icon_service_url": "",
  "_icon_service_csp": "",
  "icon_redirect_code": 302,
  "icon_cache_ttl": 2592000,
  "icon_cache_negttl": 259200,
  "icon_download_timeout": 10,
  "icon_blacklist_regex": null,
  "icon_blacklist_non_global_ips": true,
  "http_request_block_regex": null,
  "http_request_block_non_global_ips": true,
  "disable_2fa_remember": false,
  "authenticator_disable_time_drift": false,
  "experimental_client_feature_flags": "",
  "require_device_email": false,
  "reload_templates": false,
  "extended_logging": true,
  "log_timestamp_format": "%Y-%m-%d %H:%M:%S.%3f",
  "use_syslog": false,
  "log_file": null,
  "log_level": "info",
  "enable_db_wal": true,
  "db_connection_retries": 15,
  "database_timeout": 30,
  "database_idle_timeout": 600,
  "database_max_conns": 10,
  "database_min_conns": 2,
  "database_conn_init": "",
  "disable_admin_token": false,
  "allowed_iframe_ancestors": "",
  "allowed_connect_src": "",
  "login_ratelimit_seconds": 60,
  "login_ratelimit_max_burst": 10,
  "unauthenticated_ratelimit_seconds": 60,
  "unauthenticated_ratelimit_max_burst": 50,
  "admin_ratelimit_seconds": 300,
  "admin_ratelimit_max_burst": 3,
  "admin_session_lifetime": 20,
  "org_groups_enabled": false,
  "increase_note_size_limit": false,
  "_max_note_size": 10000,
  "enforce_single_org_with_reset_pw_policy": false,
  "dns_prefer_ipv6": false,
  "sso_enabled": false,
  "sso_only": false,
  "sso_signups_match_email": true,
  "sso_allow_unknown_email_verification": false,
  "sso_client_id": "",
  "sso_client_secret": "***",
  "sso_authority": "",
  "sso_scopes": "email profile",
  "sso_authorize_extra_params": "",
  "sso_pkce": true,
  "sso_audience_trusted": null,
  "sso_callback_path": "*****://*************************************************",
  "sso_master_password_policy": null,
  "sso_auth_only_not_session": false,
  "sso_client_cache_expiration": 0,
  "sso_debug_tokens": false,
  "_enable_yubico": false,
  "yubico_client_id": null,
  "yubico_secret_key": null,
  "yubico_server": null,
  "_enable_duo": false,
  "duo_use_iframe": false,
  "duo_ikey": null,
  "duo_skey": null,
  "duo_host": null,
  "_duo_akey": null,
  "_enable_smtp": true,
  "use_sendmail": false,
  "sendmail_command": null,
  "smtp_host": "*******************",
  "smtp_ssl": null,
  "smtp_explicit_tls": null,
  "smtp_security": "starttls",
  "smtp_port": 587,
  "smtp_from": "**************************",
  "smtp_from_name": "*****************",
  "smtp_username": "********************",
  "smtp_password": "***",
  "smtp_auth_mechanism": null,
  "smtp_timeout": 15,
  "helo_name": null,
  "smtp_embed_images": true,
  "_smtp_img_src": "***:",
  "smtp_debug": false,
  "smtp_accept_invalid_certs": false,
  "smtp_accept_invalid_hostnames": false,
  "_enable_email_2fa": false,
  "email_token_size": 6,
  "email_expiration_time": 600,
  "email_attempts_limit": 3,
  "email_2fa_enforce_on_verified_invite": false,
  "email_2fa_auto_fallback": false
}

But the strange thing is I let the update happen again in FF for the extension and this time it worked. I do feel there is a bug here somewhere, just not sure. If more people get the error that might help you track it down.

[BlackDex]

There is no bug, its just cached data with outdated layout which is causing the issues you had. Since the older extension works fine with this older data, it was able to continue and sync and receive the new layout, and therefore the newer version also worked fine afterwards., this is already mentioned at several other locations.

[PureOxygen-Dev]

Thanks Mathijs, sorry for the noise if this is a known issue.