diff --git a/Containerfile b/Containerfile
index ceaac4e..b43a729 100644
--- a/Containerfile
+++ b/Containerfile
@@ -1,4 +1,4 @@
-FROM docker.io/alpine:3.19 AS builder
+FROM docker.io/alpine:3.20 AS builder
 
 RUN apk add --no-cache \
   php83 \
@@ -15,19 +15,18 @@ RUN apk add --no-cache \
 
 ENV COMPOSER_VERSION=2.6.6
 ENV COMPOSER_SHA256_SUM=72600201c73c7c4b218f1c0511b36d8537963e36aafa244757f52309f885b314
-RUN wget https://getcomposer.org/download/$COMPOSER_VERSION/composer.phar
-RUN echo "$COMPOSER_SHA256_SUM  composer.phar" | sha256sum -c - || exit 1
-RUN mv composer.phar /usr/bin/composer
-RUN chmod +x /usr/bin/composer
+RUN wget https://getcomposer.org/download/$COMPOSER_VERSION/composer.phar -O /bin/composer
+RUN echo "$COMPOSER_SHA256_SUM  /bin/composer" | sha256sum -c - || exit 1
+RUN chmod +x /bin/composer
 
-ENV VERSION=1.6.5
-ENV SHA256_SUM=164b72cb78de89d104741ee9090f4024e63bfada43949034844365f3fa70b5fd
+ENV VERSION=1.6.7
+ENV SHA256_SUM=cf52515e65b2818cb02fd7a202c766367b8c54d8b7fea27dda9c81aa7ce1d3a6
 RUN wget https://github.com/roundcube/roundcubemail/releases/download/$VERSION/roundcubemail-$VERSION-complete.tar.gz
 RUN echo "$SHA256_SUM  roundcubemail-$VERSION-complete.tar.gz" | sha256sum -c - || exit 1
 RUN mkdir -p /var/lib/roundcube
 RUN tar xzf roundcubemail-$VERSION-complete.tar.gz -C /var/lib/roundcube --strip 1
 
-FROM docker.io/thallian/php8-fpm:3.19-8.3
+FROM docker.io/thallian/php8-fpm:3.20-8.3
 
 RUN apk add --no-cache \
   openssl \
diff --git a/README.md b/README.md
index bd17ad1..b7bcb42 100644
--- a/README.md
+++ b/README.md
@@ -1,73 +1,99 @@
-[Roundcube](https://roundcube.net/) webmail interface with postgres backend and oauth login.
+[Roundcube](https://roundcube.net/) webmail interface with postgres backend and
+oauth login.
 
 # Environment Variables
+
 ## DOMAINS
+
 Semicolon seperated list of domains to listen to.
 
 ## DB_USER
+
 Name of the database user.
 
 ## DB_PASSWORD
+
 Password for the database user.
 
 ## DB_HOST
+
 Database host.
 
 ## DB_NAME
+
 Database name.
 
 ## IMAP_HOST
+
 - default: tls://%n
 
 IMAP host to authenticate users against.
 
 ## SMTP_HOST
+
 - default: tls://%n
 
 SMTP host for sending mails.
 
 ## SMTP_PORT
+
 - default: 587
 
 Port for the SMTP host.
 
 ## SECRET_KEY
+
 Secret key for session secrets.
 
 ## CIPHER_METHOD
+
 - default: AES-256-CBC
 
 Encryption algorithm for session secrets.
 
 ## OAUTH_PROVIDER_NAME
+
 Name of the oauth provider on the roundcube login page.
 
 ## OAUTH_CLIENT_ID
+
 Client id for oauth login.
 
 ## OAUTH_CLIENT_SECRET
+
 Client secret for oauth login.
 
 ## OAUTH_AUTH_URI
+
 Auth uri for oauth login.
 
-Example for keycloak: `https://example.com/realms/master/protocol/openid-connect/auth`
+Example for keycloak:
+`https://example.com/realms/master/protocol/openid-connect/auth`
 
 ## OAUTH_TOKEN_URI
+
 Token uri for oauth login.
 
-Example for keycloak: `https://example.com/realms/master/protocol/openid-connect/token`
+Example for keycloak:
+`https://example.com/realms/master/protocol/openid-connect/token`
 
 ## OAUTH_IDENTITY_URI
+
 Userinfo uri for oauth login.
 
-Example for keycloak: `https://example.com/realms/master/protocol/openid-connect/userinfo`
+Example for keycloak:
+`https://example.com/realms/master/protocol/openid-connect/userinfo`
 
+## MANAGESIEVE_HOST
+
+Where to connect to managesieve.
 
 # Ports
+
 - 80
 
 # Capabilities
+
 - CHOWN
 - DAC_OVERRIDE
 - NET_BIND_SERVICE
diff --git a/rootfs/etc/confd/templates/config.inc.php.tmpl b/rootfs/etc/confd/templates/config.inc.php.tmpl
index 27d3c5e..d504c3f 100644
--- a/rootfs/etc/confd/templates/config.inc.php.tmpl
+++ b/rootfs/etc/confd/templates/config.inc.php.tmpl
@@ -36,7 +36,7 @@ $config['username_domain'] = '%d';
 $config['username_domain_forced'] = true;
 $config['password_charset'] = 'UTF-8';
 
-$config['plugins'] = array('archive', 'zipdownload');
+$config['plugins'] = array('archive', 'managesieve', 'zipdownload');
 
 $config['spellcheck_engine'] = 'pspell';
 $config['default_charset'] = 'UTF-8';
@@ -52,3 +52,4 @@ $config['oauth_scope'] = 'email profile openid';
 $config['oauth_auth_parameters'] = [];
 $config['oauth_identity_fields'] = ['preferred_username'];
 $config['oauth_login_redirect'] = true;
+$config['managesieve_host'] = '{{getenv "MANAGESIEVE_HOST"}}';