diff --git a/rwt_image_view/www/js/multi_image_viewer.js b/rwt_image_view/www/js/multi_image_viewer.js
index a782bb9d..c9be2921 100644
--- a/rwt_image_view/www/js/multi_image_viewer.js
+++ b/rwt_image_view/www/js/multi_image_viewer.js
@@ -30,7 +30,7 @@ $(function() {
 
   
   var ros = new ROSLIB.Ros();
-  ros.install_config_button("config-button");
+  ros.install_config_button("config-button", true, 9090);
 
   ros.on("connection", function() {
     ros.getTopicsForType('sensor_msgs/Image', function(image_topics) {
diff --git a/rwt_image_view/www/js/rwt_image_view_main.js b/rwt_image_view/www/js/rwt_image_view_main.js
index 86c12a52..6c3c8664 100644
--- a/rwt_image_view/www/js/rwt_image_view_main.js
+++ b/rwt_image_view/www/js/rwt_image_view_main.js
@@ -30,7 +30,7 @@ $(function() {
 
   
   var ros = new ROSLIB.Ros();
-  ros.install_config_button("config-button");
+  ros.install_config_button("config-button", true, 9090);
 
   ros.on("connection", function() {
     ros.getTopicsForType('sensor_msgs/Image', function(image_topics) {
diff --git a/rwt_utils_3rdparty/www/rwt_utils.js b/rwt_utils_3rdparty/www/rwt_utils.js
index 99be0d01..5d8c89f5 100644
--- a/rwt_utils_3rdparty/www/rwt_utils.js
+++ b/rwt_utils_3rdparty/www/rwt_utils.js
@@ -1,4 +1,4 @@
-ROSLIB.Ros.prototype.install_config_button = function(id, auto_connect) {
+ROSLIB.Ros.prototype.install_config_button = function(id, auto_connect, port=8888) {
   var auto_connect = typeof auto_connect !== 'undefined' ? auto_connect : true;
   var that = this;
   var parent = document.getElementById(id);
@@ -52,7 +52,7 @@ ROSLIB.Ros.prototype.install_config_button = function(id, auto_connect) {
   input.type = "text";
   input.pattern = "^wss?://[a-zA-Z0-9\-\._]+:[0-9]+/$";
   input.required = true;
-  input.value = "ws://" + location.hostname + ":8888/";
+  input.value = "ws://" + location.hostname + ":" + port + "/";
   input.setAttribute("class", "form-control");
   input.setAttribute("placeholder", "ROS WS Master URI");
   // input.setAttribute("aria-label", "ROS WS Master URI");