--- a/browser/base/content/browser.css
+++ b/browser/base/content/browser.css
@@ -691,16 +691,19 @@ html|*#fullscreen-warning:not([hidden]) 
 }
 html|*#fullscreen-warning[onscreen] {
   transform: translate(-50%, 50px);
 }
 html|*#fullscreen-warning[ontop] {
   /* Use -10px to hide the border and border-radius on the top */
   transform: translate(-50%, -10px);
 }
+#main-window[OSXLionFullscreen] html|*#fullscreen-warning[ontop] {
+  transform: translate(-50%, 80px);
+}
 
 html|*#fullscreen-domain-text,
 html|*#fullscreen-generic-text {
   word-wrap: break-word;
   /* We must specify a min-width, otherwise word-wrap:break-word doesn't work. Bug 630864. */
   min-width: 1px
 }
 html|*#fullscreen-domain-text:not([hidden]) + html|*#fullscreen-generic-text {