olha.js

function adicionaExcluir(){
    var arrayManager = localStorage.manager.split(',');

    $('.notific-botoes').each(function(){
        var artista = $(this).attr('data-artist');
        var notification_id = $(this).attr('data-notific');

        if(findItemArray(artista, arrayManager) == 1){
            //faz tua parada aqui
            $(this).append('<span style="margin-top: 5px; margin-left: 5px;" class="delNotification" data-id="'+notification_id+'"><i style="font-size:20px; color: #666;" class="fa fa-trash" aria-hidden="true"></i></span>');
        }else{
            alert(arrayManager);
        }
    });
}