[Bug]: Cannot generate previews for heic files since upgrade to 34.0.2

[Grokafar]

⚠️ This issue respects the following points: ⚠️

• This is a bug, not a question or a configuration/webserver/proxy issue.
• This issue is not already reported on Github OR Nextcloud Community Forum (I've searched it).
• Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• I agree to follow Nextcloud's Code of Conduct.

Bug description

The server cannot generate previews of HEIC files since the upgrade from 34.0.1 to 34.0.2 :

www-data@nextcloud:~/html$ php ./occ preview:generate [REDACTED].heic 
No preview generator available for file of typeimage/heic

www-data@nextcloud:~/html$ php ./occ preview:generate [REDACTED].heif                                                           
No preview generator available for file of typeimage/heif

Steps to reproduce

1. Upload a new HEIC file on the server
2. Generate the preview using API ou occ CLI

Expected behavior

A preview should be generated.

Nextcloud Server version

34

Operating system

Debian/Ubuntu

PHP engine version

PHP 8.5

Web server

Apache (supported)

Database engine version

MariaDB

Is this bug present after an update or on a fresh install?

Updated from a MINOR version (ex. 32.0.1 to 32.0.2)

Are you using the Nextcloud Server Encryption module?

Encryption is Disabled

What user-backends are you using?

• Default user-backend (database)
• LDAP/ Active Directory
• SSO - SAML
• Other

Configuration report

www-data@nextcloud:~/html$ php occ config:list system
{
    "system": {
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "default_phone_region": "FR",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "***REMOVED SENSITIVE VALUE***"
        ],
        "forwarded_for_headers": [
            "HTTP_X_FORWARDED_FOR"
        ],
        "trusted_proxies": "***REMOVED SENSITIVE VALUE***",
        "dbtype": "mysql",
        "version": "34.0.2.1",
        "overwrite.cli.url": "https:\/\/***REMOVED SENSITIVE VALUE***",
        "overwriteprotocol": "https",
        "overwritehost": "***REMOVED SENSITIVE VALUE***",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "memcache.local": "\\OC\\Memcache\\APCu",
        "filelocking.enabled": "true",
        "maintenance_window_start": 5,
        "memcache.distributed": "\\OC\\Memcache\\Redis",
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "password": "***REMOVED SENSITIVE VALUE***",
            "port": 6379
        },
        "enabledPreviewProviders": [
            "OC\\Preview\\PNG",
            "OC\\Preview\\JPEG",
            "OC\\Preview\\GIF",
            "OC\\Preview\\HEIC",
            "OC\\Preview\\BMP",
            "OC\\Preview\\XBitmap",
            "OC\\Preview\\MP3",
            "OC\\Preview\\TXT",
            "OC\\Preview\\MarkDown",
            "OC\\Preview\\Movie"
        ],
        "maintenance": false,
        "loglevel": 1,
        "theme": "",
        "updater.release.channel": "stable",
        "mysql.utf8mb4": true,
        "app_install_overwrite": [
            "twofactor_yubikey",
            "calendar",
            "files_downloadactivity"
        ],
        "has_rebuilt_cache": true,
        "htaccess.RewriteBase": "\/",
        "apps_paths": [
            {
                "path": "\/var\/www\/html\/apps",
                "url": "\/apps",
                "writable": false
            },
            {
                "path": "\/var\/www\/html\/custom_apps",
                "url": "\/custom_apps",
                "writable": true
            }
        ],
        "mail_smtpmode": "smtp",
        "mail_smtpsecure": "ssl",
        "mail_sendmailmode": "smtp",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpport": "465",
        "mail_smtpauth": 1,
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "memories.db.triggers.fcu": true,
        "memories.exiftool": "\/var\/www\/html\/custom_apps\/memories\/bin-ext\/exiftool-amd64-glibc",
        "memories.vod.path": "\/var\/www\/html\/custom_apps\/memories\/bin-ext\/go-vod-amd64"
    }
}

List of activated Apps

www-data@nextcloud:~/html$ php occ app:list
Enabled:
  - activity: 7.0.0
  - admin_audit: 1.24.0
  - app_api: 34.0.0
  - appstore: 1.0.0
  - calendar: 6.5.1
  - circles: 34.0.0
  - cloud_federation_api: 1.18.0
  - comments: 1.24.0
  - contacts: 8.7.4
  - contactsinteraction: 1.15.0
  - dashboard: 7.14.0
  - dav: 1.39.0
  - deck: 1.18.3
  - federatedfilesharing: 1.24.0
  - federation: 1.24.0
  - files: 2.6.0
  - files_downloadactivity: 1.18.1
  - files_downloadlimit: 5.2.0
  - files_lock: 34.0.1
  - files_pdfviewer: 7.0.0-dev.0
  - files_reminders: 1.7.0
  - files_sharing: 1.26.0
  - files_trashbin: 1.24.0
  - files_versions: 1.27.0
  - firstrunwizard: 7.0.0-dev.0
  - logreader: 7.0.0
  - lookup_server_connector: 1.22.0
  - nextcloud_announcements: 6.0.0
  - notes: 6.0.1
  - notifications: 7.0.0-dev.1
  - oauth2: 1.22.0
  - office: 1.0.0
  - password_policy: 6.0.0-dev.0
  - photos: 7.0.0
  - privacy: 6.0.0-dev.1
  - profile: 1.3.0
  - provisioning_api: 1.24.0
  - recommendations: 7.0.0
  - related_resources: 5.0.0-dev.0
  - serverinfo: 6.0.0
  - settings: 1.17.0
  - sharebymail: 1.24.0
  - spreed: 24.0.3
  - support: 6.0.0
  - survey_client: 6.0.0-dev.0
  - systemtags: 1.24.0
  - tasks: 0.18.1
  - text: 8.0.0
  - theming: 2.9.0
  - twofactor_backupcodes: 1.23.0
  - twofactor_totp: 16.0.0
  - twofactor_webauthn: 2.7.0
  - updatenotification: 1.24.0
  - user_status: 1.14.0
  - viewer: 7.0.0-dev.0
  - webhook_listeners: 1.6.0
  - workflowengine: 2.16.0
Disabled:
  - bruteforcesettings: 7.0.0 (installed 2.0.1)
  - cookbook: 0.11.6 (installed 0.11.6)
  - encryption: 2.22.0
  - files_external: 1.26.0
  - previewgenerator: 5.14.0 (installed 5.14.0)
  - suspicious_login: 12.0.0-dev.0
  - theming_customcss: 1.20.0 (installed 1.20.0)
  - twofactor_nextcloud_notification: 8.0.0
  - user_ldap: 1.25.0
  - weather_status: 1.14.0 (installed 1.12.0)

Nextcloud Signing status

No errors have been found.

Additional info

I use the docker image https://hub.docker.com/layers/library/nextcloud/34.0.2-apache
HEIF and imagemagick seems correctly installed in the image:

www-data@nextcloud:~/html$ dpkg -l | grep heif
ii  libheif-plugin-dav1d:amd64         1.19.8-1                             amd64        HEIF and AVIF file format decoder and encoder - dav1d plugin
ii  libheif-plugin-libde265:amd64      1.19.8-1                             amd64        HEIF and AVIF file format decoder and encoder - libde265 plugin
ii  libheif1:amd64                     1.19.8-1                             amd64        HEIF and AVIF file format decoder and encoder - shared library

www-data@nextcloud:~/html$ dpkg -l | grep magick
ii  imagemagick-7-common               8:7.1.1.43+dfsg1-1+deb13u11          all          image manipulation programs -- infrastructure
ii  libmagickcore-7.q16-10:amd64       8:7.1.1.43+dfsg1-1+deb13u11          amd64        low-level image manipulation library -- quantum depth Q16
ii  libmagickcore-7.q16-10-extra:amd64 8:7.1.1.43+dfsg1-1+deb13u11          amd64        low-level image manipulation library - extra codecs (Q16)
ii  libmagickwand-7.q16-10:amd64       8:7.1.1.43+dfsg1-1+deb13u11          amd64        image manipulation library -- quantum depth Q16

JPG previews are working properly 👍

www-data@nextcloud:~/html$ php ./occ preview:generate [REDACTED].jpg
preview generated

[invario]

I don't know why (and I'm not happy about it either) but this was intentional. PR #62145 disabled imagick. They said it's temporary. My guess is it's some sort of critical security flaw with ImageMagick, but it's just a guess.