JSFiddle - React, Tailwind, and code Playground
HTML
<span id="langname1">Russian</span>
<span id="langname2">French</span>
JavaScript
function setFlags() {
let languageSpans = document.querySelectorAll("span[id^=langname]");
}
(async function() {
(document.readyState !== 'loading') ?
setFlags() : document.addEventListener('DOMContentLoaded',
function() {
setFlags(); // EventHandler
});
})();