diff --git a/src/support.js b/src/support.js
index f039c7e8..50ae6dfd 100644
--- a/src/support.js
+++ b/src/support.js
@@ -66,7 +66,7 @@ jQuery.support = (function() {
 		// Make sure that if no value is specified for a checkbox
 		// that it defaults to "on".
 		// (WebKit defaults to "" instead)
-		checkOn: input.value === "on",
+		checkOn: ( input.value === "on" ),
 
 		// Make sure that a selected-by-default option has a working selected property.
 		// (WebKit defaults to false instead of true, IE too, if it's in an optgroup)
@@ -75,6 +75,7 @@ jQuery.support = (function() {
 		// Will be defined later
 		submitBubbles: true,
 		changeBubbles: true,
+		focusinBubbles: false,
 		deleteExpando: true,
 		noCloneEvent: true,
 		inlineBlockNeedsLayout: false,