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addOnloadHook(function () {
    var rights_isAdmin = (mw.config.get('wgUserGroups').toString().indexOf('sysop') != -1);
    if (!rights_isAdmin)
        return; //Restrict to admins.
    if (mw.config.get('wgNamespaceNumber') != "2" && mw.config.get('wgNamespaceNumber') != "3")
        return;  // restrict to User and User talk

    var title = mw.config.get('wgTitle');

    mw.util.addPortletLink('p-tb', '/wiki/Special:Userrights/'+title,
                   'User rights', 't-userrights', 'User rights for "'+title+'"');

});