Document environment variables

Uwe Grawert · Uwe Grawert · commit 776fa2ad956a · 2019-07-16T10:02:11.000+02:00
diff --git a/README.md b/README.md
@@ -15,6 +15,17 @@ This image launches Firefox with support for Java Webstart applications.
 docker pull ugrawert/firefox-java:latest
 ```
 
+## Environment variables
+
+The following environment variables can be passed via `docker run -e`.
+
+| Variable  | Explanation                 | Example                |
+| --------- | --------------------------- | ---------------------- |
+| DISPLAY   | The X11 display port to use | DISPLAY=:1             |
+| URL       | Firefox opens this URL      | URL=http://google.com/ |
+| uid       | Run Firefox with this uid   | uid=$(id -u)           |
+| gid       | Run Firefox with this gid   | gid=$(id -u)           |
+
 ## Run
 
 ```sh
@@ -27,7 +38,6 @@ docker run --rm -ti \
            -v "${HOME}/Downloads:/home/firefox/Downloads:rw" \
            -v "/tmp/.X11-unix:/tmp/.X11-unix" \
            -v "/dev/snd:/dev/snd" \
-           --privileged \
            -e "DISPLAY=unix${DISPLAY}" \
            -e "uid=$(id -u)" \
            -e "gid=$(id -g)" \
