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mw.hook('wikipage.content').add(function() {
    var personalTools = document.getElementById('p-personal');
    if (personalTools) {
        var ul = personalTools.querySelector('ul');
        var sandboxLi = ul.querySelector('li#pt-sandbox');
        
        if (sandboxLi) {
            var todoesLink = document.createElement('li');
            todoesLink.id = 'pt-todoes';
            todoesLink.innerHTML = '<a href="/wiki/Special:MyPage/Todoes">Todoes</a>';
            
            sandboxLi.insertAdjacentElement('afterend', todoesLink);
        }
    }
});