diff --git a/common/content/commandline.js b/common/content/commandline.js
index caf18a57..149b5c33 100644
--- a/common/content/commandline.js
+++ b/common/content/commandline.js
@@ -725,6 +725,9 @@ var CommandLine = Module("commandline", {
 
         if (flags & this.APPEND_TO_MESSAGES) {
             let message = isObject(data) ? data : { message: data };
+
+            // Make sure the memoized message property is an instance property.
+            message.message;
             this._messageHistory.add(update({ highlight: highlightGroup }, message));
             data = message.message;
         }
diff --git a/common/modules/addons.jsm b/common/modules/addons.jsm
index 3b3fa7ce..a22b2842 100644
--- a/common/modules/addons.jsm
+++ b/common/modules/addons.jsm
@@ -59,12 +59,13 @@ var updateAddons = Class("UpgradeListener", AddonListener, {
 
     },
     onUpdateAvailable: function (addon, install) {
+        util.dump("onUpdateAvailable");
         this.upgrade.push(addon);
         install.addListener(this);
         install.install();
     },
     onUpdateFinished: function (addon, error) {
-        this.remaining = this.remaining.filter(function (a) a != addon);
+        this.remaining = this.remaining.filter(function (a) a.type != addon.type || a.id != addon.id);
         if (!this.remaining.length)
             this.dactyl.echomsg(
                 this.upgrade.length