Error with sfcp access

Hello,
With the external storage app, I wish connect with sfcp.
I green icon look good so i can connect to the remote server, but i can’t access to the files.

This is the log error

Error: Trying to access array offset on value of type bool at /var/www/localhost/nextcloud/apps/files_external/lib/Lib/Storage/SFTP.php#334
{"reqId":"82viEJ6MnrCEz4fDWCNE","level":3,"time":"2020-10-09T18:05:01+00:00","remoteAddr":"","user":"--","app":"PHP","method":"","url":"--","message":{"Exception":"Error","Message":"Trying to access array offset on value of type bool at /var/www/localhost/nextcloud/apps/files_external/lib/Lib/Storage/SFTP.php#334","Code":0,"Trace":[{"file":"/var/www/localhost/nextcloud/apps/files_external/lib/Lib/Storage/SFTP.php","line":334,"function":"onError","class":"OC\\Log\\ErrorHandler","type":"::"},{"file":"/var/www/localhost/nextcloud/lib/private/Files/Storage/Common.php","line":114,"function":"filetype","class":"OCA\\Files_External\\Lib\\Storage\\SFTP","type":"->"},{"file":"/var/www/localhost/nextcloud/lib/private/Files/Storage/Common.php","line":148,"function":"is_dir","class":"OC\\Files\\Storage\\Common","type":"->"},{"file":"/var/www/localhost/nextcloud/lib/private/Files/Storage/Common.php","line":168,"function":"isCreatable","class":"OC\\Files\\Storage\\Common","type":"->"},{"file":"/var/www/localhost/nextcloud/lib/private/Files/Storage/Common.php","line":703,"function":"getPermissions","class":"OC\\Files\\Storage\\Common","type":"->"},{"file":"/var/www/localhost/nextcloud/lib/private/Files/Storage/Wrapper/Wrapper.php","line":583,"function":"getMetaData","class":"OC\\Files\\Storage\\Common","type":"->"},{"file":"/var/www/localhost/nextcloud/lib/private/Files/Storage/Wrapper/Availability.php","line":444,"function":"getMetaData","class":"OC\\Files\\Storage\\Wrapper\\Wrapper","type":"->"},{"file":"/var/www/localhost/nextcloud/lib/private/Files/Storage/Wrapper/Wrapper.php","line":583,"function":"getMetaData","class":"OC\\Files\\Storage\\Wrapper\\Availability","type":"->"},{"file":"/var/www/localhost/nextcloud/lib/private/Files/Cache/Scanner.php","line":114,"function":"getMetaData","class":"OC\\Files\\Storage\\Wrapper\\Wrapper","type":"->"},{"file":"/var/www/localhost/nextcloud/lib/private/Files/Cache/Scanner.php","line":152,"function":"getData","class":"OC\\Files\\Cache\\Scanner","type":"->"},{"file":"/var/www/localhost/nextcloud/lib/private/Files/Cache/Scanner.php","line":338,"function":"scanFile","class":"OC\\Files\\Cache\\Scanner","type":"->"},{"file":"/var/www/localhost/nextcloud/lib/private/Files/Cache/Scanner.php","line":500,"function":"scan","class":"OC\\Files\\Cache\\Scanner","type":"->"},{"file":"/var/www/localhost/nextcloud/lib/private/Files/Cache/Scanner.php","line":517,"function":"OC\\Files\\Cache\\{closure}","class":"OC\\Files\\Cache\\Scanner","type":"->","args":["*** sensitive parameters replaced ***"]},{"file":"/var/www/localhost/nextcloud/lib/private/Files/Cache/Scanner.php","line":501,"function":"runBackgroundScanJob","class":"OC\\Files\\Cache\\Scanner","type":"->"},{"file":"/var/www/localhost/nextcloud/lib/private/Files/Utils/Scanner.php","line":186,"function":"backgroundScan","class":"OC\\Files\\Cache\\Scanner","type":"->"},{"file":"/var/www/localhost/nextcloud/apps/files/lib/BackgroundJob/ScanFiles.php","line":83,"function":"backgroundScan","class":"OC\\Files\\Utils\\Scanner","type":"->"},{"file":"/var/www/localhost/nextcloud/apps/files/lib/BackgroundJob/ScanFiles.php","line":111,"function":"runScanner","class":"OCA\\Files\\BackgroundJob\\ScanFiles","type":"->"},{"file":"/var/www/localhost/nextcloud/lib/private/BackgroundJob/Job.php","line":52,"function":"run","class":"OCA\\Files\\BackgroundJob\\ScanFiles","type":"->"},{"file":"/var/www/localhost/nextcloud/lib/private/BackgroundJob/TimedJob.php","line":59,"function":"execute","class":"OC\\BackgroundJob\\Job","type":"->"},{"file":"/var/www/localhost/nextcloud/cron.php","line":126,"function":"execute","class":"OC\\BackgroundJob\\TimedJob","type":"->"}],"File":"/var/www/localhost/nextcloud/lib/private/Log/ErrorHandler.php","Line":91,"CustomMessage":"--"},"userAgent":"--","version":"20.0.0.9","id":"5f80a64d2076a"}

Nextcloud version : 20
Operating system and version : alpinelinux edge
Apache or nginx version : Nginx 1.18.0
PHP version : 7.4.11

Steps to replicate it:

  1. simple sftp connexion with ssh key

The output of your config.php file in /path/to/nextcloud

<?php
$CONFIG = array (
  'instanceid' => 'instanceid',
  'passwordsalt' => 'x1OLt/passwordsalt',
  'secret' => 'secret',
  'trusted_domains' =>
  array (
    0 => '192.168.0.201',
    1 => '192.168.0.250',
    2 => 'cloud.exemple.com',
  ),
  'datadirectory' => '/mnt/noth-nas01/vm-data',
  'dbtype' => 'pgsql',
  'version' => '20.0.0.9',
  'overwrite.cli.url' => 'https://cloud.exemple.com',
  'dbname' => 'nextcloud',
  'dbhost' => 'localhost',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'dbuser' => 'dbuser',
  'dbpassword' => 'dbpassword',
  'installed' => true,
  'overwritehost' => 'cloud.domaine.com',
  'overwriteprotocol' => 'https',
  'default_language' => 'fr',
  'skeletondirectory' => 'var/www/localhost/nextcloud/core/skeleton',
  'memcache.local' => '\\OC\\Memcache\\APCu',
  'memcache.locking' => '\\OC\\Memcache\\Redis',
  'redis' =>
  array (
    'host' => 'localhost',
    'port' => 6379,
  ),
  'app_install_overwrite' =>
  array (
    0 => 'camerarawpreviews',
    1 => 'gluusso',
    2 => 'user_external',
    3 => 'ldaporg',
  ),
  'ldapIgnoreNamingRules' => false,
  'ldapProviderFactory' => 'OCA\\User_LDAP\\LDAPProviderFactory',
);

The output of your Apache/nginx/system log in /var/log/____:

nothing usuful