diff --git a/core/connection.js b/core/connection.js
index 1728576a6..d245c3548 100644
--- a/core/connection.js
+++ b/core/connection.js
@@ -180,8 +180,9 @@ Blockly.Connection.prototype.connect_ = function(childConnection) {
       // block.  Since this block may be a stack, walk down to the end.
       var newBlock = childBlock;
       while (newBlock.nextConnection) {
-        if (newBlock.nextConnection.isConnected()) {
-          newBlock = newBlock.getNextBlock();
+        var nextBlock = newBlock.getNextBlock();
+        if (nextBlock && !nextBlock.isShadow()) {
+          newBlock = nextBlock;
         } else {
           if (orphanBlock.previousConnection.checkType_(
               newBlock.nextConnection)) {
diff --git a/tests/multi_playground.html b/tests/multi_playground.html
index c25d7a543..f541d6f6b 100644
--- a/tests/multi_playground.html
+++ b/tests/multi_playground.html
@@ -161,7 +161,7 @@ h1 {
   </xml>
 
   <xml id="toolbox-categories" style="display: none">
-     <category name="Logic" colour="210">
+    <category name="Logic" colour="210">
       <block type="controls_if"></block>
       <block type="logic_compare"></block>
       <block type="logic_operation"></block>