diff --git a/contrib/docker/Dockerfile.dovecot b/contrib/docker/Dockerfile.dovecot
index 89a2ddbf..309b9765 100644
--- a/contrib/docker/Dockerfile.dovecot
+++ b/contrib/docker/Dockerfile.dovecot
@@ -1,7 +1,6 @@
 FROM debian:12-slim
 
-ENV container=docker \
-    LC_ALL=C
+ENV LC_ALL=C
 ARG DEBIAN_FRONTEND=noninteractive
 
 RUN apt-get -y update && apt-get -y install \