JSFiddle - React, Tailwind, and code Playground

HTML

<input type="submit" id="edit-submit" name="op" value="Save" class="form-submit">
<input type="submit" value="Submit it!" class="form-submit">
<input type="submit" value="Go">

JavaScript

var inputs = document.getElementsByTagName('input');
for (var i = 0, il = inputs.length; i < il; i++) {
  if (inputs[i].type.toLowerCase() == 'submit') {
    inputs[i].value = '\u2714 ' + inputs[i].value;
  }
}