In Material-UI (MUI) TextField, we can have both a label and a placeholder, but when the text field is empty, we can only see the label. We have to start editing the TextField in order to see the placeholder. Is there a way to say that both the label and placeholder should show initially when the field is empty? We'd also like to style the placeholder slightly differently by making it slightly gray compared to the black label text color. Is there a way to do this?