Bug 558585 - Window flashes white when a new tab is made, despite settings. r=gavin

browser/base/content/tabbrowser.css

@@ -35,7 +35,7 @@
 }
 
 tabpanels {
-  background-color: white;
+  background-color: transparent;
 }
 
 .tab-drop-indicator {

browser/base/content/tabbrowser.xml

@@ -2456,6 +2456,11 @@
           this.mTabListeners[0] = tabListener;
           this.mTabFilters[0] = filter;
           this.init();
+
+          this.style.backgroundColor =
+            Services.prefs.getBoolPref("browser.display.use_system_colors") ?
+              "-moz-default-background-color" :
+              Services.prefs.getCharPref("browser.display.background_color");
         ]]>
       </constructor>