diff --git a/browser/base/content/browser.xul b/browser/base/content/browser.xul
index 22dbcdf979a2..f1084c568b7f 100644
--- a/browser/base/content/browser.xul
+++ b/browser/base/content/browser.xul
@@ -320,7 +320,7 @@
          <observes element="viewTabsSidebar" attribute="checked"/>
        </toolbarbutton>
       <toolbarseparator/>
-      <toolbarbutton label="&sidebarCloseButton.tooltip;"
+      <toolbarbutton label="&sidebarMenuClose.label;"
                      class="subviewbutton"
                      oncommand="SidebarUI.hide()"/>
     </panel>
diff --git a/browser/locales/en-US/chrome/browser/browser.dtd b/browser/locales/en-US/chrome/browser/browser.dtd
index 5ff27100559a..0e07f5ac485e 100644
--- a/browser/locales/en-US/chrome/browser/browser.dtd
+++ b/browser/locales/en-US/chrome/browser/browser.dtd
@@ -667,6 +667,7 @@ you can use these alternative items. Otherwise, their values should be empty.  -
 <!ENTITY fullZoom.accesskey             "Z">
 
 <!ENTITY sidebarCloseButton.tooltip     "Close sidebar">
+<!ENTITY sidebarMenuClose.label         "Close Sidebar">
 
 <!ENTITY quitApplicationCmdWin2.label       "Exit">
 <!ENTITY quitApplicationCmdWin2.accesskey   "x">