--- a/addon-sdk/source/lib/sdk/event/chrome.js
+++ b/addon-sdk/source/lib/sdk/event/chrome.js
@@ -52,14 +52,14 @@ function observe(topic) {
   // observerChannel (since third argument is `true`). There for if it
   // will be GC-ed with all it's event listeners once no other references
   // will be held.
   addObserver(observerChannel, topic, true);
 
   // We need to remove any observer added once the add-on is unloaded;
   // otherwise we'll get a "dead object" exception.
   // See: https://bugzilla.mozilla.org/show_bug.cgi?id=1001833
-  unload(() => removeObserver(observerChannel, topic), { weak: true });
+  unload(() => removeObserver(observerChannel, topic));
 
   return observerChannel;
 }
 
 exports.observe = observe;