--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@@ -1609,25 +1609,31 @@ function BrowserCloseTabOrWindow()
 #ifdef XP_MACOSX
   // If we're not a browser window, just close the window
   if (window.location.href != getBrowserURL()) {
     closeWindow(true);
     return;
   }
 #endif
 
-  if (gBrowser.tabContainer.childNodes.length > 1 ||
-      window.toolbar.visible && !gPrefService.getBoolPref("browser.tabs.autoHide")) {
-    // Just close the tab (and focus the address bar if it was the last one).
-    var isLastTab = gBrowser.tabContainer.childNodes.length == 1;
+  if (gBrowser.tabContainer.childNodes.length > 1) {
+    gBrowser.removeCurrentTab(); 
+    return;
+  }
+
+#ifndef XP_MACOSX
+  if (gBrowser.localName == "tabbrowser" && window.toolbar.visible &&
+      !gPrefService.getBoolPref("browser.tabs.autoHide")) {
+    // Replace the remaining tab with a blank one and focus the address bar
     gBrowser.removeCurrentTab();
-    if (isLastTab && gURLBar)
+    if (gURLBar)
       setTimeout(function() { gURLBar.focus(); }, 0);
     return;
   }
+#endif
 
   closeWindow(true);
 }
 
 function BrowserTryToCloseWindow()
 {
   if (WindowIsClosing())
     window.close();     // WindowIsClosing does all the necessary checks