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Polymer · Nov 5, 2015 · f2d5f44 · f2d5f44
1 parent da71dfe
commit f2d5f44
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/src/standard/utils.html b/src/standard/utils.html
@@ -233,6 +233,11 @@
 
     __eventCache: {},
 
+    // NOTE: We optionally cache event objects for efficiency during high
+    // freq. opts. This option cannot be used for events which may have 
+    // `stopPropagation` called on them. On Chrome and Safari (but not FF)
+    // if `stopPropagation` is called, the event cannot be reused. It does not 
+    // dispatch again.
     _getEvent: function(type, bubbles, cancelable, useCache) {
       var event = useCache && this.__eventCache[type];
       if (!event || ((event.bubbles != bubbles) ||