--- a/mobile/android/modules/geckoview/Messaging.jsm
+++ b/mobile/android/modules/geckoview/Messaging.jsm
@@ -107,20 +107,31 @@ DispatcherDelegate.prototype = {
    * @param aMsg Message to send; must be an object with a "type" property
    * @return A Promise resolving to the response
    */
   sendRequestForResult: function(aMsg) {
     return new Promise((resolve, reject) => {
       const type = aMsg.type;
       aMsg.type = undefined;
 
-      this.dispatch(type, aMsg, {
-        onSuccess: resolve,
-        onError: reject,
-      });
+      // Manually release the resolve/reject functions after one callback is
+      // received, so the JS GC is not tied up with the Java GC.
+      const onCallback = (callback, ...args) => {
+        if (callback) {
+          callback(...args);
+        }
+        resolve = undefined;
+        reject = undefined;
+      };
+      const callback = {
+        onSuccess: result => onCallback(resolve, result),
+        onError: error => onCallback(reject, error),
+        onFinalize: _ => onCallback(reject),
+      };
+      this.dispatch(type, aMsg, callback, callback);
     });
   },
 
   finalize: function() {
     if (!this._replies) {
       return;
     }
     this._replies.forEach(reply => {