add a visual bell and replace 'beep' with 'visualbell'

chrome/content/vimperator/default.css

@@ -165,6 +165,11 @@ fieldset.paypal {
     overflow: hidden;
 }
 
+#vimperator-visualbell {
+    background-color: blue;
+    opacity: 0.5;
+}
+
 .status_insecure, .status_insecure * {
     background-color: transparent;
 }

chrome/content/vimperator/events.js

@@ -80,7 +80,7 @@ function Events() //{{{
 
     function enterPopupMode(event)
     {
-        if (event.originalTarget.localName == "tooltip")
+        if (event.originalTarget.localName == "tooltip" || event.originalTarget.id == "vimperator-visualbell")
             return;
 
         vimperator.addMode(null, vimperator.modes.MENU);

chrome/content/vimperator/options.js

@@ -343,12 +343,6 @@ function Options() //{{{
             default_value: "homepage,quickmark,tabopen,paste"
         }
     ));
-    addOption(new Option(["beep"], "boolean",
-        {
-            short_help: "Emit a pc speaker beep on certain errors",
-            default_value: true
-        }
-    ));
     addOption(new Option(["complete", "cpt"], "charlist",
         {
             short_help: "Items which are completed at the :[tab]open prompt",
@@ -547,6 +541,12 @@ function Options() //{{{
             validator: function (value) { if (value >= 0 && value <= 9) return true; else return false; }
         }
     ));
+    addOption(new Option(["visualbell", "vb"], "boolean",
+        {
+            short_help: "Use visual bell instead of beeping on errors",
+            default_value: false
+        }
+    ));
     addOption(new Option(["wildmode", "wim"], "stringlist",
         {
             short_help: "Define how command line completion works",

chrome/content/vimperator/vimperator.js

@@ -280,8 +280,22 @@ const vimperator = (function() //{{{
 
         beep: function()
         {
-            if (vimperator.options["beep"])
+            if (!vimperator.options["visualbell"])
+            {
                 sound_service.beep();
+                return;
+            }
+
+            // flash the visual bell
+            var popup = document.getElementById("vimperator-visualbell");
+            var win = document.getElementById("main-window");
+            var box = document.getBoxObjectFor(win);
+
+            popup.height = box.height;
+            popup.width = box.width;
+            popup.showPopup(win, box.screenX, box.screenY, "popup");
+
+            setTimeout(function() { popup.hidePopup(); }, 375);
         },
 
         copyToClipboard: function(str)

chrome/content/vimperator/vimperator.xul

@@ -116,6 +116,11 @@ the terms of any one of the MPL, the GPL or the LGPL.
            <key id="key_stop" keycode="VK_ESCAPE" oncommand="vimperator.events.onEscape();"/>
            <!-- other keys are handled inside vimperator.js event loop -->
         </keyset>
+
+        <popupset id="vimperator-popupset">
+            <popup id="vimperator-visualbell"/>
+        </popupset>
+
     </window>
 </overlay>