I did this using 2 buttons and negative margin space but I’d rather use 1 button. The first button’s text says “Language” and the the other uses the down arrow as the text.

How to add the down arrow special character &#9660 to data-translate?

<button data-translate="select_language"></button>

translator = {
    en: {
        select_language: "Language &#9660" // this obviously doesn't work
    },
    fr: {
        select_languae: "Langue &#9660"
    }
}