diff --git a/assets/css/styles.scss b/assets/css/styles.scss
index 2e8da6c47..ec5240a09 100644
--- a/assets/css/styles.scss
+++ b/assets/css/styles.scss
@@ -278,6 +278,10 @@ ol li {
   background-color: #B71C1C;
 }
 
+.missing-data-response {
+  background-color: #676767;
+}
+
 fieldset#history {
   .method-list-item {
     position: relative;
diff --git a/pages/index.vue b/pages/index.vue
index d9f0acc77..495f28c7d 100644
--- a/pages/index.vue
+++ b/pages/index.vue
@@ -249,6 +249,13 @@
       statusCodeRegex: new RegExp(/[5][0-9]+/),
       className: 'sv-error-response'
     },
+    {
+      // this object is a catch-all for when no other objects match and should always be last
+      name: 'unknown',
+      statusCodeRegex: new RegExp(/.*/),
+      className: 'missing-data-response'
+    }
+
   ];
   const parseHeaders = xhr => {
     const headers = xhr.getAllResponseHeaders().trim().split(/[\r\n]+/);