| Index: pkg/browser/lib/interop.js
 | 
| diff --git a/pkg/browser/lib/interop.js b/pkg/browser/lib/interop.js
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| index 1caeb5a209937eb0967c211bd0bc1e4a8a59926b..c88a0a46cadab541df82421bf312477e798410b5 100644
 | 
| --- a/pkg/browser/lib/interop.js
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| +++ b/pkg/browser/lib/interop.js
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| @@ -164,7 +164,7 @@ function DartObject(o) {
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|      delete ReceivePortSync.map[this.id];
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|    };
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|  
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| -  if (navigator.webkitStartDart) {
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| +  if (navigator.userAgent.indexOf('(Dart)') !== -1) {
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|      window.addEventListener('js-sync-message', function(event) {
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|        var data = JSON.parse(getPortSyncEventData(event));
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|        var deserialized = deserialize(data.message);
 | 
| 
 |