fix(postiz): use localhost instead of docker hostname for backend_internal_url

the internal nginx in postiz container requires localhost, not the docker
service name, as this url is used for proxying within the container itself.

CHANGELOG.md

@@ -2,6 +2,11 @@
 
 ## [Unreleased]
 
+## [1.2.4] - 2026-01-30
+
+### Fixed
+- **Postiz** - Fix `BACKEND_INTERNAL_URL` to use `localhost` instead of Docker hostname (internal nginx requires localhost)
+
 ## [1.2.3] - 2026-01-29
 
 ### Fixed

docker-compose.yml

@@ -836,7 +836,7 @@ services:
     restart: always
     environment:
       <<: *proxy-env
-      BACKEND_INTERNAL_URL: http://postiz:3000
+      BACKEND_INTERNAL_URL: http://localhost:3000
       DATABASE_URL: "postgresql://postgres:${POSTGRES_PASSWORD}@postgres:5432/${POSTIZ_DB_NAME:-postiz}?schema=postiz"
       DISABLE_REGISTRATION: ${POSTIZ_DISABLE_REGISTRATION}
       FRONTEND_URL: ${POSTIZ_HOSTNAME:+https://}${POSTIZ_HOSTNAME}