Describe the issue

Earlier today, an update for the Docker container (version 5.13) was pushed which broke my existing Weblate installation. I run Weblate in a Docker container on unRAID using Apache2 on a separate host on the same local network with a letsencrypt SSL certificate as a reverse proxy with ProxyPreserveHost enabled. However, with update 5.13 the website started to send the users into a redirect loop with the browser saying 'the website tried to redirect you too many times,' which I only managed to fix by downgrading to 5.12. The host I used is set as the site domain using the appropriate environment variable (WEBLATE_SITE_DOMAIN, iirc) and I did use HTTPS with Weblate also being setup to do so using the appropriate environment variable.

Something that may be worth to note is that going to the local IP (192.168.178.3:8040) redirects to the actual hostname properly using HTTPS on both versions.

I already tried

• I've read and searched the documentation.
• I've searched for similar filed issues in this repository.

Steps to reproduce the behavior

1. Install and setup Weblate 5.12 through a Docker container.
2. Setup a reverse proxy (Apache 2 in my case). Might be optional, but cannot verify due to the current setup.
3. Verify that Weblate is accessible.
4. Upgrade to 5.13.
5. Weblate is no longer accessible and we are now thrown into a redirect loop.

Expected behavior

I should be able to access the Weblate instance just fine.

Screenshots

No response

Exception traceback

How do you run Weblate?

Docker container

Weblate versions

• Weblate: 5.13
• Django: 5.2.5
• siphashc: 2.5
• translate-toolkit: 3.15.6
• lxml: 6.0.0
• pillow: 11.3.0
• nh3: 0.3.0
• python-dateutil: 2.9.0.post0
• social-auth-core: 4.7.0
• social-auth-app-django: 5.5.1
• django-crispy-forms: 2.4
• oauthlib: 3.3.1
• django-compressor: 4.5.1
• djangorestframework: 3.16.1
• django-filter: 25.1
• django-appconf: 1.1.0
• user-agents: 2.2.0
• filelock: 3.19.1
• RapidFuzz: 3.13.0
• openpyxl: 3.1.5
• celery: 5.5.3
• django-celery-beat: 2.8.1
• kombu: 5.5.4
• translation-finder: 2.23
• weblate-language-data: 2025.8
• html2text: 2025.4.15
• pycairo: 1.28.0
• PyGObject: 3.52.3
• diff-match-patch: 20241021
• requests: 2.32.4
• django-redis: 6.0.0
• hiredis: 3.2.1
• sentry-sdk: 2.35.0
• Cython: 3.1.3
• mistletoe: 1.4.0
• GitPython: 3.1.45
• borgbackup: 1.4.1
• pyparsing: 3.2.3
• ahocorasick_rs: 0.22.2
• charset-normalizer: 3.4.3
• cyrtranslit: 1.1.1
• drf-spectacular: 0.28.0
• Python: 3.13.3
• Git: 2.50.1
• psycopg: 3.2.9
• psycopg-binary: 3.2.9
• phply: 1.2.6
• ruamel.yaml: 0.18.14
• tesserocr: 2.8.0
• boto3: 1.40.10
• aeidon: 1.15
• iniparse: 0.5
• mysqlclient: 2.2.7
• google-cloud-translate: 3.21.1
• openai: 1.99.9
• Mercurial: 7.1
• git-svn: 2.50.1
• git-review: 2.5.0
• Redis server: 8.2.0
• PostgreSQL server: 17.6
• Database backends: django.db.backends.postgresql
• PostgreSQL implementation: psycopg3 (binary)
• Cache backends: default:RedisCache, avatar:FileBasedCache
• Email setup: django.core.mail.backends.dummy.EmailBackend: localhost
• OS encoding: filesystem=utf-8, default=utf-8
• Celery: redis://192.168.178.3:6379/1, redis://192.168.178.3:6379/1, regular
• Platform: Linux 6.12.24-Unraid (x86_64)

Weblate deploy checks

SystemCheckError: System check identified some issues:

CRITICALS:
?: (weblate.E027) The path /app/data/ssh/known_hosts is owned by a different user, check your DATA_DIR settings.
        HINT: https://docs.weblate.org/en/weblate-5.12.2/admin/install.html#file-permissions

ERRORS:
?: (weblate.E011) E-mail addresses for site admins is misconfigured
        HINT: https://docs.weblate.org/en/weblate-5.12.2/admin/install.html#production-admins

INFOS:
?: (weblate.I021) Error collection is not set up, it is highly recommended for production use
        HINT: https://docs.weblate.org/en/weblate-5.12.2/admin/install.html#collecting-errors
?: (weblate.I028) Backups are not configured, it is highly recommended for production use
        HINT: https://docs.weblate.org/en/weblate-5.12.2/admin/backup.html
?: (weblate.I031) New Weblate version is available, please upgrade to 5.13.
        HINT: https://docs.weblate.org/en/weblate-5.12.2/admin/upgrade.html

System check identified 5 issues (5 silenced).

Additional context

No response