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function ocultarElementos() {
    var elementos = document.querySelectorAll('.user-id');
    elementos.forEach(function(elemento) {
        elemento.style.display = 'none';
    });
}

var observer = new MutationObserver(function(mutations) {
    mutations.forEach(function(mutation) {
        if (mutation.addedNodes.length > 0) {
            ocultarElementos();
        }
    });
});

observer.observe(document.body, { childList: true, subtree: true });