diff --git a/README.md b/README.md
index acc8725..e12b456 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,7 @@
 6. Create `.env` with `$ cp sample.env .env`
 7. Adjust the values in `.env`
    - **Important:** don't forget to change `ETHERPAD_API_KEY`, `SHARED_SECRET` and `RAILS_SECRET` to any random values! For example generated with `pwgen 40 3`
-   - `DOMAIN` and `EXTERNAL_IP` are also required
+   - `DOMAIN` and `EXTERNAL_IP` are also required. For example, use `dig +short <DOMAIN>` to get your external ip address. 
 8. Start container. either...
     - **Most common setup**: BigBlueButton with automatic HTTPS certificate retrieval and Greenlight
         ```bash
@@ -83,8 +83,16 @@ docker-compose up -d
 # greenlight & https image updates
 ```
 
+## Special thanks to
+- @dkrenn, whos dockerized version (bigbluebutton#8858)(https://github.com/bigbluebutton/bigbluebutton/pull/8858) helped me a lot in understand and some configs.
+
 ## Open Tasks
 - add support for recording
 - add coturn support
 - further separate bbb-core into individual container
-
+- enable IPv6 support
+- fix captions (they don't appear, `readOnlyPadId` is missing)
+- switch to `node:12-buster-slim` for `html5`
+- switch to `node:12-buster-slim` for `webrtc-sfu` 
+- drop root privileges in `webrtc-sfu`
+- drop root privileges in `kurento`
diff --git a/mod/core/Dockerfile b/mod/core/Dockerfile
index 2598848..fe131bc 100644
--- a/mod/core/Dockerfile
+++ b/mod/core/Dockerfile
@@ -45,9 +45,6 @@ RUN apt-get update && apt-get install -y bbb-web \
 # https://github.com/bigbluebutton/bigbluebutton/issues/8959
 RUN sed -i 's|securerandom.source=file:/dev/random|securerandom.source=file:/dev/urandom|g'  /usr/lib/jvm/java-8-openjdk-amd64/jre/lib/security/java.security
 
-# -- fix directory permissions
-RUN chown bigbluebutton:bigbluebutton /var/bigbluebutton
-
 # -- copy configuration files
 COPY red5-webapps/bigbluebutton/application.conf /usr/share/red5/webapps/bigbluebutton/WEB-INF/classes/application.conf
 COPY red5-webapps/bigbluebutton/bigbluebutton.properties /usr/share/red5/webapps/bigbluebutton/WEB-INF/bigbluebutton.properties
diff --git a/mod/core/entrypoint.sh b/mod/core/entrypoint.sh
index b4cd40b..a1bd364 100755
--- a/mod/core/entrypoint.sh
+++ b/mod/core/entrypoint.sh
@@ -13,6 +13,8 @@ mkdir -p /var/bigbluebutton/published
 mkdir -p /var/bigbluebutton/deleted
 mkdir -p /var/bigbluebutton/unpublished
 
+# -- fix directory permissions
+RUN chown bigbluebutton:bigbluebutton /var/bigbluebutton
 
 dockerize \
     -template /usr/share/bbb-web/WEB-INF/classes/bigbluebutton.properties.tmpl:/usr/share/bbb-web/WEB-INF/classes/bigbluebutton.properties \