diff --git a/_common/KeymanHosts.php b/_common/KeymanHosts.php
index 651270d..0a1fc36 100644
--- a/_common/KeymanHosts.php
+++ b/_common/KeymanHosts.php
@@ -83,6 +83,36 @@ public function fixupHostReferences($contents) {
       return $contents;
     }
 
+    /**
+     * Return a Javascript snippet that defines the Keyman website hostnames for
+     * the current environment, which should be injected into a SCRIPT element
+     * near the top of the document.
+     */
+    public function emitJavascriptConst() {
+      echo <<<END
+        const keymanHosts = {
+          ['s.keyman.com']: "$this->s_keyman_com",
+          ['api.keyman.com']: "$this->api_keyman_com",
+          ['help.keyman.com']: "$this->help_keyman_com",
+          ['keyman.com']: "$this->keyman_com",
+          ['keymanweb.com']: "$this->keymanweb_com",
+          ['downloads.keyman.com']: "$this->downloads_keyman_com",
+          ['blog.keyman.com']: "$this->blog_keyman_com",
+          ['translate.keyman.com']: "$this->translate_keyman_com",
+          ['r.keymanweb.com']: "$this->r_keymanweb_com",
+          s: "$this->s_keyman_com",
+          api: "$this->api_keyman_com",
+          help: "$this->help_keyman_com",
+          keyman: "$this->keyman_com",
+          keymanweb: "$this->keymanweb_com",
+          downloads: "$this->downloads_keyman_com",
+          blog: "$this->blog_keyman_com",
+          translate: "$this->translate_keyman_com",
+          r_keymanweb: "$this->r_keymanweb_com",
+        };
+END;
+    }
+
     public function overrideHost($host, $value) {
       if(empty($this->$host)) {
         // If there's no value set, then we must be overriding something invalid
diff --git a/_common/docker.inc.sh b/_common/docker.inc.sh
index 40bd966..f52764b 100644
--- a/_common/docker.inc.sh
+++ b/_common/docker.inc.sh
@@ -82,6 +82,7 @@ function start_docker_container() {
   local CONTAINER_ID=$(get_docker_container_id $CONTAINER_NAME)
   if [ ! -z "$CONTAINER_ID" ]; then
     builder_echo green "Container $CONTAINER_ID has already been started, listening on http://$HOST:$PORT"
+    return 0
   fi
 
   # Start the Docker container