dmstern

function isVisible(element) {
    const style = window.getComputedStyle(element);
    return style.display !== 'none';
}

function isFocusable (element) {
    const focusableElements = [
    'a[href]',
    'button:enabled',
    'input:enabled',

bvaughn

function setFocusIfFocusable(node) {
  if (node.nodeType !== Node.ELEMENT_NODE) {
    // Text and comment nodes aren't focusable.
    return false;
  }

  if (node.disabled === true) {
    // Disabled elements can't be focused.
    return false;
  }