diff --git a/Dockerfile b/Dockerfile
index 4ab0d86..48ed0d8 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -6,7 +6,7 @@ RUN apt-get update && apt-get install -y \
   xvfb \
   curl \
   bzip2 \
-  libgtk-3-dev \ 
+  libgtk-3-dev \
   wget
 
 RUN wget -q -O - https://dl-ssl.google.com/linux/linux_signing_key.pub | apt-key add -
@@ -16,10 +16,17 @@ RUN sh -c 'echo "deb [arch=amd64] http://dl.google.com/linux/chrome/deb/ stable
 RUN apt-get update && apt-get install -y \
   google-chrome-stable
 
+RUN mkdir -p /opt/firefox/46.0.1
 RUN curl -SL https://ftp.mozilla.org/pub/firefox/releases/46.0.1/linux-x86_64/en-US/firefox-46.0.1.tar.bz2 \
-  | tar -xjC /opt
+  | tar -xjC /opt/firefox/46.0.1
 
-RUN ln -s /opt/firefox/firefox /usr/bin/firefox
+RUN mkdir -p /opt/firefox/53.0.3
+RUN curl -SL https://ftp.mozilla.org/pub/firefox/releases/53.0.3/linux-x86_64/en-US/firefox-53.0.3.tar.bz2 \
+    | tar -xjC /opt/firefox/53.0.3
+
+COPY firefox.sh /usr/bin/firefox
+
+RUN chmod +x /usr/bin/firefox
 
 COPY google-chrome.sh /usr/bin/google-chrome
 
diff --git a/firefox.sh b/firefox.sh
new file mode 100644
index 0000000..7193eab
--- /dev/null
+++ b/firefox.sh
@@ -0,0 +1,5 @@
+#!/bin/bash
+
+: ${FIREFOX_VERSION:=46.0.1}
+
+/opt/firefox/$FIREFOX_VERSION/firefox/firefox "$@"