--- a/browser/base/content/browser-menubar.inc
+++ b/browser/base/content/browser-menubar.inc
@@ -207,16 +207,17 @@
                     <menuitem id="menu_bookmarksSidebar"
                               key="viewBookmarksSidebarKb"
                               observes="viewBookmarksSidebar"/>
                     <menuitem id="menu_historySidebar"
                               key="key_gotoHistory"
                               observes="viewHistorySidebar"
                               label="&historyButton.label;"/>
                     <menuitem id="menu_tabsSidebar"
+                              class="sync-ui-item"
                               observes="viewTabsSidebar"
                               label="&syncedTabs.sidebar.label;"/>
                   </menupopup>
                 </menu>
                 <menuseparator/>
                 <menu id="viewFullZoomMenu" label="&fullZoom.label;"
                       accesskey="&fullZoom.accesskey;"
                       onpopupshowing="FullZoom.updateMenu();">

--- a/browser/base/content/browser.xul
+++ b/browser/base/content/browser.xul
@@ -293,17 +293,17 @@
                      class="subviewbutton subviewbutton-iconic"
                      key="key_gotoHistory"
                      observes="viewHistorySidebar"
                      oncommand="SidebarUI.show('viewHistorySidebar');">
         <observes element="viewHistorySidebar" attribute="checked"/>
       </toolbarbutton>
       <toolbarbutton id="sidebar-switcher-tabs"
                      label="&syncedTabs.sidebar.label;"
-                     class="subviewbutton subviewbutton-iconic"
+                     class="subviewbutton subviewbutton-iconic sync-ui-item"
                      observes="viewTabsSidebar"
                      oncommand="SidebarUI.show('viewTabsSidebar');">
         <observes element="viewTabsSidebar" attribute="checked"/>
       </toolbarbutton>
       <toolbarseparator/>
       <!-- Extension toolbarbuttons go here. -->
       <toolbarseparator id="sidebar-extensions-separator"/>
       <toolbarbutton id="sidebar-reverse-position"