src/language-handlebars/printer-glimmer.js/clean
function clean(ast, newObj) {
  // (Glimmer/HTML) ignore TextNode whitespace
  if (ast.type === "TextNode") {
    if (ast.chars.replace(/\s+/, "") === "") {
      return null;
    }
    newObj.chars = ast.chars.replace(/^\s+/, "").replace(/\s+$/, "");
  }
}