diff --git a/content/completion.js b/content/completion.js
index bd5eaa47..af1a4aeb 100644
--- a/content/completion.js
+++ b/content/completion.js
@@ -187,7 +187,6 @@ CompletionContext.prototype = {
     },
     set generate(arg)
     {
-        let self = this;
         this.hasItems = true;
         this._generate = arg;
         if (this.background && this.regenerate)
@@ -195,12 +194,14 @@ CompletionContext.prototype = {
             let lock = {};
             this.cache.backgroundLock = lock;
             this.incomplete = true;
-            liberator.callFunctionInThread(null, function () {
-                let items = self.generate();
-                if (self.cache.backgroundLock != lock)
+            liberator.dump({name: this.name, length: this.items.length});
+            let now = Date.now();
+            liberator.callAsync(this, function () {
+                let items = this.generate();
+                if (this.cache.backgroundLock != lock)
                     return;
-                self.incomplete = false;
-                self.completions = items;
+                this.incomplete = false;
+                this.completions = items;
             });
         }
     },
@@ -231,7 +232,7 @@ CompletionContext.prototype = {
             return this.cache.filtered;
         this.cache.rows = [];
         let items = this.completions;
-        if (this.generate)
+        if (this.generate && !this.background)
         {
             // XXX
             let updateAsync = this.updateAsync;
@@ -1230,6 +1231,7 @@ function Completion() //{{{
                 context.advance(dir.length);
             context.keys = { text: 0, description: 1, icon: 2 };
             context.anchored = true;
+            context.background = true;
             context.key = dir;
             context.generate = function generate_file()
             {
diff --git a/content/liberator.js b/content/liberator.js
index d5d940e0..8e380205 100644
--- a/content/liberator.js
+++ b/content/liberator.js
@@ -26,6 +26,8 @@ the provisions above, a recipient may use your version of this file under
 the terms of any one of the MPL, the GPL or the LGPL.
 }}} ***** END LICENSE BLOCK *****/
 
+Components.utils.import("resource://gre/modules/XPCOMUtils.jsm");
+
 const plugins = {};
 plugins.__proto__ = modules;
 
@@ -37,6 +39,16 @@ const liberator = (function () //{{{
 
     const threadManager = Components.classes["@mozilla.org/thread-manager;1"]
                                     .getService(Components.interfaces.nsIThreadManager);
+    function Runnable(self, func, args)
+    {
+        this.self = self;
+        this.func = func;
+        this.args = args;
+    }
+    Runnable.prototype = {
+        QueryInterface: XPCOMUtils.generateQI([Components.interfaces.nsIRunnable]),
+        run: function () { this.func.apply(this.self, this.args); }
+    };
 
     var callbacks = [];
     var observers = [];
@@ -628,32 +640,20 @@ const liberator = (function () //{{{
             return false; // so you can do: if (...) return liberator.beep();
         },
 
+        callAsync: function (self, func)
+        {
+            let thread = threadManager.newThread(0);
+            thread.dispatch(new Runnable(self, func, Array.slice(arguments, 2)), thread.DISPATCH_NORMAL);
+        },
+
         // be sure to call GUI related methods like alert() or dump() ONLY in the main thread
         callFunctionInThread: function (thread, func)
         {
-            function CallbackEvent(func, args)
-            {
-                return {
-                    QueryInterface: function (iid)
-                    {
-                        if (iid.equals(Components.interfaces.nsIRunnable) ||
-                            iid.equals(Components.interfaces.nsISupports))
-                            return this;
-                        throw Components.results.NS_ERROR_NO_INTERFACE;
-                    },
-
-                    run: function ()
-                    {
-                        func.apply(window, args);
-                    }
-                };
-            }
-
             if (!thread)
                 thread = threadManager.newThread(0);
 
             // DISPATCH_SYNC is necessary, otherwise strange things will happen
-            thread.dispatch(new CallbackEvent(func, Array.slice(arguments, 2)), thread.DISPATCH_SYNC);
+            thread.dispatch(new Runnable(null, func, Array.slice(arguments, 2)), thread.DISPATCH_SYNC);
         },
 
         // NOTE: "browser.dom.window.dump.enabled" preference needs to be set
@@ -663,7 +663,7 @@ const liberator = (function () //{{{
                 message = util.objectToString(message);
             else
                 message += "\n";
-            dump(("config" in modules && config.name.toLowerCase()) + ": " + message);
+            window.dump(("config" in modules && config.name.toLowerCase()) + ": " + message);
         },
 
         dumpStack: function (msg)
diff --git a/content/style.js b/content/style.js
index 8aa5be5a..c0d851a1 100644
--- a/content/style.js
+++ b/content/style.js
@@ -6,8 +6,6 @@
  it under any or all of those licenseses.
 }}} ***** END LICENSE BLOCK *****/
 
-Components.utils.import("resource://gre/modules/XPCOMUtils.jsm");
-
 function Highlights(name, store, serial)
 {
     const highlightCSS = <![CDATA[