Small frame for html mails

Nextcloud version (eg, 20.0.5): 24.0.2 on docker image

The issue you are facing:
With mail 1.13.5, I know have a short preview of HTML mails:

Since not everybody using mail is reporting the issue, I consider there is a configuration/caching/conflict issue on my side.

But I have no idea where to start

Is this the first time you’ve seen this error? (Y/N): yes

Steps to replicate it:

  1. Open an HTML email in mail application

The output of your Nextcloud log in Admin > Logging:

Summary
Level	App	Message		Time
Error	mail	OCA\Mail\Exception\ServiceException: Could not load classifier 703: /appdata_ocuhp5rdzzf2/mail/classifiers/703		2022-06-26T22:45:43+0200
Error	PHP	Error: Trying to access array offset on value of type bool at /var/www/html/custom_apps/mail/vendor/bytestream/horde-imap-client/lib/Horde/Imap/Client/Base.php#761		2022-06-26T21:48:10+0200
Error	mail	OCA\Mail\Exception\ServiceException: Could not load classifier 703: /appdata_ocuhp5rdzzf2/mail/classifiers/703		2022-06-26T21:48:04+0200
Error	PHP	Error: Trying to access array offset on value of type bool at /var/www/html/custom_apps/mail/vendor/bytestream/horde-imap-client/lib/Horde/Imap/Client/Base.php#761		2022-06-26T20:48:09+0200
Error	PHP	Error: Trying to access array offset on value of type bool at /var/www/html/custom_apps/mail/vendor/bytestream/horde-imap-client/lib/Horde/Imap/Client/Base.php#761		2022-06-26T19:48:05+0200
Error	PHP	Error: Trying to access array offset on value of type bool at /var/www/html/custom_apps/mail/vendor/bytestream/horde-imap-client/lib/Horde/Imap/Client/Base.php#761		2022-06-26T18:36:09+0200
Error	mail	OCA\Mail\Exception\ServiceException: Could not load classifier 1800: /appdata_ocuhp5rdzzf2/mail/classifiers/1800		2022-06-26T18:36:06+0200
Error	PHP	Error: Trying to access array offset on value of type bool at /var/www/html/custom_apps/mail/vendor/bytestream/horde-imap-client/lib/Horde/Imap/Client/Base.php#761		2022-06-26T17:24:11+0200
Error	PHP	Error: Trying to access array offset on value of type bool at /var/www/html/custom_apps/mail/vendor/bytestream/horde-imap-client/lib/Horde/Imap/Client/Base.php#761		2022-06-26T16:12:09+0200
Error	PHP	Error: Trying to access array offset on value of type bool at /var/www/html/custom_apps/mail/vendor/bytestream/horde-imap-client/lib/Horde/Imap/Client/Base.php#761		2022-06-26T15:00:11+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 9: Error connecting to mail server.		2022-06-26T13:58:43+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 8: Error connecting to mail server.		2022-06-26T13:57:23+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 7: Error connecting to mail server.		2022-06-26T13:56:03+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 6: Error connecting to mail server.		2022-06-26T13:54:42+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 4: Error connecting to mail server.		2022-06-26T13:53:22+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 3: Error connecting to mail server.		2022-06-26T13:52:02+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 2: Error connecting to mail server.		2022-06-26T13:50:42+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 1: Error connecting to mail server.		2022-06-26T13:49:22+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 9: Error connecting to mail server.		2022-06-26T12:46:43+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 8: Error connecting to mail server.		2022-06-26T12:45:23+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 7: Error connecting to mail server.		2022-06-26T12:44:03+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 6: Error connecting to mail server.		2022-06-26T12:42:43+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 4: Error connecting to mail server.		2022-06-26T12:41:23+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 3: Error connecting to mail server.		2022-06-26T12:40:03+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 2: Error connecting to mail server.		2022-06-26T12:38:42+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 1: Error connecting to mail server.		2022-06-26T12:37:22+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 9: Error connecting to mail server.		2022-06-26T11:34:44+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 8: Error connecting to mail server.		2022-06-26T11:33:23+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 7: Error connecting to mail server.		2022-06-26T11:32:03+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 6: Error connecting to mail server.		2022-06-26T11:30:43+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 4: Error connecting to mail server.		2022-06-26T11:29:23+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 3: Error connecting to mail server.		2022-06-26T11:28:03+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 2: Error connecting to mail server.		2022-06-26T11:26:43+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 1: Error connecting to mail server.		2022-06-26T11:25:23+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 9: Error connecting to mail server.		2022-06-26T10:34:43+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 8: Error connecting to mail server.		2022-06-26T10:33:23+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 7: Error connecting to mail server.		2022-06-26T10:32:02+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 6: Error connecting to mail server.		2022-06-26T10:30:42+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 4: Error connecting to mail server.		2022-06-26T10:29:22+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 3: Error connecting to mail server.		2022-06-26T10:28:02+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 2: Error connecting to mail server.		2022-06-26T10:26:42+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 1: Error connecting to mail server.		2022-06-26T10:25:22+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 9: Error connecting to mail server.		2022-06-26T09:22:43+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 8: Error connecting to mail server.		2022-06-26T09:21:23+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 7: Error connecting to mail server.		2022-06-26T09:20:02+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 6: Error connecting to mail server.		2022-06-26T09:18:42+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 4: Error connecting to mail server.		2022-06-26T09:17:22+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 3: Error connecting to mail server.		2022-06-26T09:16:02+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 2: Error connecting to mail server.		2022-06-26T09:14:42+0200
Error	mail	OCA\Mail\Exception\ServiceException: IMAP error synchronizing account 1: Error connecting to mail server.		2022-06-26T09:13:22+0200

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

$CONFIG = array (
  'instanceid' => 'ocuhp5rdzzf2',
  'passwordsalt' => 'salt',
  'secret' => 'pepper',
  'trusted_domains' => 
  array (
    0 => 'xxx',
    1 => 'yyyy',
    2 => 'zzz',
  ),
  'datadirectory' => '/var/www/data',
  'dbtype' => 'mysql',
  'version' => '24.0.2.1',
  'overwrite.cli.url' => 'https://xxx.local',
  'dbname' => 'nextcloud',
  'dbhost' => 'nextcloud-mariadb',
  'dbport' => '3306',
  'dbtableprefix' => 'oc_',
  'mysql.utf8mb4' => true,
  'dbuser' => 'nextcloud',
  'dbpassword' => 'db',
  'installed' => true,
  'activity_expire_days' => 14,
  'auth.bruteforce.protection.enabled' => true,
  'blacklisted_files' => 
  array (
    0 => '.htaccess',
    1 => 'Thumbs.db',
    2 => 'thumbs.db',
  ),
  'cron_log' => true,
  'enable_previews' => true,
  'enabledPreviewProviders' => 
  array (
    0 => 'OC\\Preview\\PNG',
    1 => 'OC\\Preview\\JPEG',
    2 => 'OC\\Preview\\GIF',
    3 => 'OC\\Preview\\BMP',
    4 => 'OC\\Preview\\XBitmap',
    5 => 'OC\\Preview\\Movie',
    6 => 'OC\\Preview\\PDF',
    7 => 'OC\\Preview\\MP3',
    8 => 'OC\\Preview\\TXT',
    9 => 'OC\\Preview\\MarkDown',
  ),
  'filesystem_check_changes' => 0,
  'filelocking.enabled' => 'true',
  'htaccess.RewriteBase' => '/',
  'integrity.check.disabled' => false,
  'knowledgebaseenabled' => false,
  'log_rotate_size' => 104857600,
  'logtimezone' => 'Europe/Berlin',
  'memcache.local' => '\\OC\\Memcache\\APCu',
  'memcache.locking' => '\\OC\\Memcache\\Redis',
  'preview_max_x' => 1024,
  'preview_max_y' => 768,
  'preview_max_scale_factor' => 1,
  'redis' => 
  array (
    'host' => 'nextcloud-redis',
    'port' => 6379,
    'timeout' => 0.0,
    'password' => '',
  ),
  'quota_include_external_storage' => false,
  'share_folder' => '/Shares',
  'skeletondirectory' => '',
  'trashbin_retention_obligation' => 'auto, 7',
  'maintenance' => false,
  'loglevel' => 2,
  'mail_smtpmode' => 'smtp',
  'mail_sendmailmode' => 'pipe',
  'mail_from_address' => 'from',
  'mail_domain' => 'domain',
  'mail_smtphost' => 'dns',
  'mail_smtpport' => '25',
  'theme' => '',
  'apps_paths' => 
  array (
    0 => 
    array (
      'path' => '/var/www/html/apps',
      'url' => '/apps',
      'writable' => false,
    ),
    1 => 
    array (
      'path' => '/var/www/html/custom_apps',
      'url' => '/custom_apps',
      'writable' => true,
    ),
  ),
  'trusted_proxies' => 
  array (
    0 => '192.168.x.xxx',
  ),
);

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

None since in docker, apache log is redirected to /dev/stderr

Output errors in nextcloud.log in /var/www/ or as admin user in top right menu, filtering for errors. Use a pastebin service if necessary.

no errors shown in docker-compose logs

Any help welcome !

Mathias

Fixed with Mail 1.13.5