enforce_theme not working when unauthenticated

[b-bittner]

⚠️ 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

When 'enforce_theme' => 'light' is set in config.php, the theme is just enforced for logged in users.
At the login screen or in a link-shared-folder, the theme is not enforced.

Steps to reproduce

1. fresh (docker) installation
2. set 'enforce_theme' => 'light', in config.php
3. open login site or a link-shared folder from a client with dark-mode preferred browser

Expected behavior

I would expect that the setting forces the theme system wide, even when not authenticated.

Installation method

Community Docker image

Nextcloud Server version

26

Operating system

Other

PHP engine version

Other

Web server

Other

Database engine version

MariaDB

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

Fresh Nextcloud Server install

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@a85221577a51:~/html$ php occ config:list system
{
    "system": {
        "htaccess.RewriteBase": "\/",
        "memcache.local": "\\OC\\Memcache\\APCu",
        "apps_paths": [
            {
                "path": "\/var\/www\/html\/apps",
                "url": "\/apps",
                "writable": false
            },
            {
                "path": "\/var\/www\/html\/custom_apps",
                "url": "\/custom_apps",
                "writable": true
            }
        ],
        "overwritehost": "nc26.weblab.avateam.com",
        "overwriteprotocol": "https",
        "trusted_proxies": "***REMOVED SENSITIVE VALUE***",
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "nc26.weblab.avateam.com"
        ],
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "dbtype": "mysql",
        "version": "26.0.3.2",
        "overwrite.cli.url": "https:\/\/nc26.weblab.avateam.com",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "mysql.utf8mb4": true,
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "default_phone_region": "DE",
        "simpleSignUpLink.shown": false,
        "skeletondirectory": "empty",
        "force_language": "de_DE",
        "default_locale": "de_DE",
        "default_language": "de",
        "trashbin_retention_obligation": "auto, 30",
        "enforce_theme": "light"
    }
}
www-data@a85221577a51:~/html$

List of activated Apps

www-data@a85221577a51:~/html$ php occ app:list
Enabled:
  - activity: 2.18.0
  - circles: 26.0.0
  - cloud_federation_api: 1.9.0
  - comments: 1.16.0
  - contactsinteraction: 1.7.0
  - dashboard: 7.6.0
  - dav: 1.25.0
  - federatedfilesharing: 1.16.0
  - federation: 1.16.0
  - files: 1.21.1
  - files_pdfviewer: 2.7.0
  - files_rightclick: 1.5.0
  - files_sharing: 1.18.0
  - files_trashbin: 1.16.0
  - files_versions: 1.19.1
  - firstrunwizard: 2.15.0
  - logreader: 2.11.0
  - lookup_server_connector: 1.14.0
  - nextcloud_announcements: 1.15.0
  - notifications: 2.14.0
  - oauth2: 1.14.0
  - password_policy: 1.16.0
  - photos: 2.2.0
  - privacy: 1.10.0
  - provisioning_api: 1.16.0
  - recommendations: 1.5.0
  - related_resources: 1.1.0-alpha1
  - serverinfo: 1.16.0
  - settings: 1.8.0
  - sharebymail: 1.16.0
  - support: 1.9.0
  - survey_client: 1.14.0
  - systemtags: 1.16.0
  - text: 3.7.2
  - theming: 2.1.1
  - twofactor_backupcodes: 1.15.0
  - updatenotification: 1.16.0
  - user_status: 1.6.0
  - viewer: 1.10.0
  - weather_status: 1.6.0
  - workflowengine: 2.8.0
Disabled:
  - admin_audit: 1.16.0
  - bruteforcesettings: 2.6.0
  - encryption: 2.14.0
  - files_external: 1.18.0
  - suspicious_login: 4.4.0
  - twofactor_totp: 8.0.0
  - user_ldap: 1.16.0

Nextcloud Signing status

No errors have been found.

Nextcloud Logs

No response

Additional info

Docker-Image-Name: nextcloud:26

[joshtrichards]

Fixed in #45875