$("#worker1_date1").popover({
    html: true,
    content:" <span>Task 1: 6h. Approved: False <button id='btn_worker1_date1' class='btn btn-success btn-sm'>Approve</button></span> <span>Task 2: 2h. Approved: True <button id='btn_worker1_date2' class='btn btn-danger btn-sm'> Disapprove</button></span>",
});

// This works
document.querySelector("#worker1_date1").textContent = "Modified Text"

// This does not work
document.querySelector("#btn_worker1_date1").textContent = "Modified Text"