Event: add support comment

Ref gh-2047

diff --git a/src/event.js b/src/event.js
index ee0af6179076abe3efb8acbd8746997e77186136..0aa37ec6e5160c63a3b320304e79da93f5a049fe 100644 (file)
--- a/src/event.js
+++ b/src/event.js
@@ -26,6 +26,8 @@ function returnFalse() {
        return false;
 }
 
+// Support: IE9
+// See #13393 for more info
 function safeActiveElement() {
        try {
                return document.activeElement;
@@ -424,8 +426,11 @@ jQuery.event = {
                        delegateCount = handlers.delegateCount,
                        cur = event.target;
 
+               // Support (at least): Chrome, IE9
                // Find delegate handlers
                // Black-hole SVG <use> instance trees (#13180)
+               //
+               // Support: Firefox
                // Avoid non-left-click bubbling in Firefox (#3861)
                if ( delegateCount && cur.nodeType && (!event.button || event.type !== "click") ) {
 
@@ -626,6 +631,7 @@ jQuery.event = {
 };
 
 jQuery.removeEvent = function( elem, type, handle ) {
+       // This "if" is needed for plain objects
        if ( elem.removeEventListener ) {
                elem.removeEventListener( type, handle, false );
        }