diff --git a/components.html b/components.html
index d213030bbf..a632194444 100644
--- a/components.html
+++ b/components.html
@@ -1856,7 +1856,7 @@ body { padding-bottom: 70px; }
       <div class="row">
         <div class="col-lg-4">
           <div class="thumbnail">
-            <img data-src="holder.js/300x200" alt="" src="data:image/png;base64,">
+            <img data-src="holder.js/300x200" alt="Generic placeholder thumbnail" src="data:image/png;base64,">
             <div class="caption">
               <h3>Thumbnail label</h3>
               <p>Cras justo odio, dapibus ac facilisis in, egestas eget quam. Donec id elit non mi porta gravida at eget metus. Nullam id dolor id nibh ultricies vehicula ut id elit.</p>
@@ -1866,7 +1866,7 @@ body { padding-bottom: 70px; }
         </div>
         <div class="col-lg-4">
           <div class="thumbnail">
-            <img data-src="holder.js/300x200" alt="" src="data:image/png;base64,">
+            <img data-src="holder.js/300x200" alt="Generic placeholder thumbnail" src="data:image/png;base64,">
             <div class="caption">
               <h3>Thumbnail label</h3>
               <p>Cras justo odio, dapibus ac facilisis in, egestas eget quam. Donec id elit non mi porta gravida at eget metus. Nullam id dolor id nibh ultricies vehicula ut id elit.</p>
@@ -1876,7 +1876,7 @@ body { padding-bottom: 70px; }
         </div>
         <div class="col-lg-4">
           <div class="thumbnail">
-            <img data-src="holder.js/300x200" alt="" src="data:image/png;base64,">
+            <img data-src="holder.js/300x200" alt="Generic placeholder thumbnail" src="data:image/png;base64,">
             <div class="caption">
               <h3>Thumbnail label</h3>
               <p>Cras justo odio, dapibus ac facilisis in, egestas eget quam. Donec id elit non mi porta gravida at eget metus. Nullam id dolor id nibh ultricies vehicula ut id elit.</p>
@@ -1890,7 +1890,7 @@ body { padding-bottom: 70px; }
 <div class="row">
   <div class="col-lg-4">
     <div class="thumbnail">
-      <img data-src="holder.js/300x200" alt="">
+      <img data-src="holder.js/300x200" alt="...">
       <div class="caption">
         <h3>Thumbnail label</h3>
         <p>...</p>