Hidden elements - focus test

These buttons are hidden in different ways. Let's see if they are focusable!

Button Two is hidden using CSS display:none. It isn't expected to be focusable. Focus will jump from Button 1 to Button 3.

Button Four is hidden using CSS visibility:hidden. It has space reserved, so this paragraph is indented. It isn't expected to be focusable. Focus will jump from Button 3 to Button 5

Button 6 is hidden "off-viewport" with negative positioning. Even though we can't see it, we can focus on it.

Button 8 is hidden using a .visuallyhidden class technique, similar to HTML5 boilerplate or Drupal8. Even though we can't see it, we can focus on it.

Button 10 is hidden using CSS opacity:0; Even though we can't see it, we can focus on it.

Button 12 is hidden using the HTML hidden attribute. This usually gets treated the same as using CSS display:none. Focus should jump from Button 11 to Button 13.