diff --git a/core/css.js b/core/css.js
index 94a75f723..66a789e9b 100644
--- a/core/css.js
+++ b/core/css.js
@@ -584,6 +584,7 @@ Blockly.Css.CONTENT = [
 
   '.blocklyContextMenu {',
     'border-radius: 4px;',
+    'max-height: 100%;',
   '}',
 
   '.blocklyDropdownMenu {',
diff --git a/core/widgetdiv.js b/core/widgetdiv.js
index 8edad91ff..b51dc5e8d 100644
--- a/core/widgetdiv.js
+++ b/core/widgetdiv.js
@@ -186,7 +186,12 @@ Blockly.WidgetDiv.positionWithAnchor = function(viewportBBox, anchorBBox,
   var x = Blockly.WidgetDiv.calculateX_(viewportBBox, anchorBBox, widgetSize,
       rtl);
 
-  Blockly.WidgetDiv.positionInternal_(x, y, widgetSize.height);
+  if (y < 0) {
+    Blockly.WidgetDiv.positionInternal_(x, 0, widgetSize.height + y);
+  }
+  else {
+    Blockly.WidgetDiv.positionInternal_(x, y, widgetSize.height);
+  }
 };
 
 /**