diff --git a/content/completion.js b/content/completion.js
index 4b54ee83..2e8d4620 100644
--- a/content/completion.js
+++ b/content/completion.js
@@ -58,11 +58,6 @@ function Completion() //{{{
     var completionCache = [];
 
     var historyTimer = new util.Timer(50, 100, function histTimer() {
-        // don't set all completions again every time the timer fires, even
-        // though items might not have changed
-        if (historyCache.length == historyResult.matchCount)
-            return;
-
         let comp = [];
         for (let i in util.range(0, historyResult.matchCount))
             comp.push([historyResult.getValueAt(i),
@@ -73,7 +68,8 @@ function Completion() //{{{
 
         // TODO: we need to have a "completionCacheAfter" to allow cpt=slf 
         historyCache = comp;
-        commandline.setCompletions({ get items() { return completionCache.concat(historyCache); } });
+        commandline.setCompletions({ get items() completionCache.concat(historyCache),
+                                     incompleteResult: historyResult.searchResult >= historyResult.RESULT_NOMATCH_ONGOING ? true : false });
     });
 
     function Javascript()
@@ -1319,7 +1315,8 @@ function Completion() //{{{
                 }
             }
 
-            return { start: start, items: completions, getMoreItems: getMoreItems };
+            // TODO: incomplete result should be set conditionally
+            return { start: start, items: completions, getMoreItems: getMoreItems, incompleteResult: true };
         },
 
         userCommand: function userCommand(filter)
diff --git a/content/ui.js b/content/ui.js
index a4a4649c..a9756ec1 100644
--- a/content/ui.js
+++ b/content/ui.js
@@ -1227,10 +1227,9 @@ function CommandLine() //{{{
             if (liberator.mode != modes.COMMAND_LINE)
                 return;
 
-            /* Only hide if not pending.
-            if (compl.length == 0)
-                return completionList.hide();
-            */
+            // don't show an empty result, if we are just waiting for data to arrive
+            if (newCompletions.incompleteResult && newCompletions.items.length == 0)
+                return;
 
             completionList.setItems(newCompletions.items);
 
@@ -1258,7 +1257,6 @@ function CommandLine() //{{{
             var command = this.getCommand();
             completionPrefix = command.substring(0, commandWidget.selectionStart);
             completionPostfix = command.substring(commandWidget.selectionStart);
-
         },
 
         // TODO: does that function need to be public?
@@ -1266,7 +1264,7 @@ function CommandLine() //{{{
         {
             autocompleteTimer.reset();
             completion.cancel();
-            completions = { start: 0, items: [] };
+            completions = { start: completions.start, items: [] };
             completionIndex = historyIndex = UNINITIALIZED;
             wildIndex = 0;
         }