[Bug]: Custom Theming throws error

[197788]

⚠️ 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 only errors I get are because I'm using a non-default theme. It is throwing an error about it . (ScssPhp)

Steps to reproduce

1. Clear cookies and logfile; now login.
2. Watch an error thrown in nextcloud.log

Expected behavior

No errors should happen

Nextcloud Server version

31

Operating system

Debian/Ubuntu

PHP engine version

PHP 8.4

Web server

Nginx

Database engine version

PostgreSQL

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

{
    "system": {
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "nextcloud.marinaro.cc"
        ],
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "dbtype": "pgsql",
        "version": "31.0.4.1",
        "overwrite.cli.url": "https:\/\/nextcloud.marinaro.cc",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "skeletondirectory": "",
        "maintenance_window_start": 1,
        "memcache.local": "\\OC\\Memcache\\Redis",
        "memcache.distributed": "\\OC\\Memcache\\Redis",
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "port": 0,
            "timeout": 0,
            "read_timeout": 0
        },
        "default_phone_region": "US",
        "logtimezone": "America\/Phoenix",
        "maintenance": false,
        "data-fingerprint": "6bb2e7f791b290911e4fd54e1ab8ea86",
        "theme": "",
        "token_auth_enforced": "true",
        "twofactor_enforced": "true",
        "twofactor_enforced_groups": [],
        "twofactor_enforced_excluded_groups": [],
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpmode": "smtp",
        "mail_sendmailmode": "smtp",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpauth": true,
        "mail_smtpport": "587",
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "loglevel": 3,
        "tempdirectory": "\/tmp\/",
        "files.chunked_upload.max_size": 20971520
    }
}

List of activated Apps

Enabled:
  - activity: 4.0.0
  - app_api: 5.0.2
  - bruteforcesettings: 4.0.0
  - circles: 31.0.0
  - cloud_federation_api: 1.14.0
  - comments: 1.21.0
  - contactsinteraction: 1.12.0
  - dashboard: 7.11.0
  - dav: 1.33.0
  - federatedfilesharing: 1.21.0
  - federation: 1.21.0
  - files: 2.3.1
  - files_downloadlimit: 4.0.0
  - files_pdfviewer: 4.0.0
  - files_reminders: 1.4.0
  - files_sharing: 1.23.1
  - files_trashbin: 1.21.0
  - files_versions: 1.24.0
  - firstrunwizard: 4.0.0
  - logreader: 4.0.0
  - lookup_server_connector: 1.19.0
  - nextcloud_announcements: 3.0.0
  - notifications: 4.0.0
  - oauth2: 1.19.1
  - password_policy: 3.0.0
  - photos: 4.0.0-dev.1
  - privacy: 3.0.0
  - profile: 1.0.0
  - provisioning_api: 1.21.0
  - recommendations: 4.0.0
  - related_resources: 2.0.0
  - serverinfo: 3.0.0
  - settings: 1.14.0
  - sharebymail: 1.21.0
  - support: 3.0.0
  - survey_client: 3.0.0
  - systemtags: 1.21.1
  - text: 5.0.0
  - theming: 2.6.1
  - twofactor_backupcodes: 1.20.0
  - twofactor_totp: 13.0.0-dev.0
  - updatenotification: 1.21.0
  - user_status: 1.11.0
  - viewer: 4.0.0
  - weather_status: 1.11.0
  - webhook_listeners: 1.2.0
  - workflowengine: 2.13.0
Disabled:
  - admin_audit: 1.21.0
  - encryption: 2.19.0
  - files_external: 1.23.0
  - suspicious_login: 9.0.1
  - twofactor_nextcloud_notification: 5.0.0
  - user_ldap: 1.22.0

Nextcloud Signing status

No errors have been found.

Nextcloud Logs

{"reqId":"Eq0Gsh95IA5UCVYL7RGl","level":3,"time":"2025-04-27T17:45:58-07:00","remoteAddr":"127.0.0.1","user":false,"app":"PHP","method":"GET","url":"/apps/theming/theme/light.css?plain=0&v=0ed0b2ec","message":"ScssPhp\\ScssPhp\\Warn::setCallback(): Implicitly marking parameter $callback as nullable is deprecated, the explicit nullable type must be used instead at /var/www/nextcloud/3rdparty/scssphp/scssphp/src/Warn.php#62","userAgent":"Mozilla/5.0 (X11; Linux x86_64; rv:137.0) Gecko/20100101 Firefox/137.0","version":"31.0.4.1","data":{"app":"PHP"}}




{"reqId":"I9cno477Og0lEPBzkEBe","level":3,"time":"2025-04-27T17:45:58-07:00","remoteAddr":"127.0.0.1","user":false,"app":"PHP","method":"GET","url":"/apps/theming/theme/light-highcontrast.css?plain=0&v=0ed0b2ec","message":"ScssPhp\\ScssPhp\\Node\\Number::output(): Implicitly marking parameter $compiler as nullable is deprecated, the explicit nullable type must be used instead at /var/www/nextcloud/3rdparty/scssphp/scssphp/src/Node/Number.php#581","userAgent":"Mozilla/5.0 (X11; Linux x86_64; rv:137.0) Gecko/20100101 Firefox/137.0","version":"31.0.4.1","data":{"app":"PHP"}}

Additional info

The errors above are two errors, but looks like the same area of operation: "theming".
I am using custom colors for the default theme, and also users are using their own custom themes.

[susnux]

The reason for this is using PHP 8.4.
The error should not cause any damage as only a fallback mechanism is not working correctly with PHP 8.4 in the theming due to lack of support in a dependency we use.

[susnux]

Fixed in next maintenance releases in May