Valid values:

contents

These elements don't produce a specific box by themselves. They are replaced by their pseudo-box and their child boxes. Please note that the CSS Display Level 3 spec defines how the contents value should affect "unusual elements" — elements that aren't rendered purely by CSS box concepts such as replaced elements. See Appendix B: Effects of display: contents on Unusual Elements for more details.

Due to a bug in browsers this will currently remove the element from the accessibility tree — screen readers will not look at what's inside. See the Accessibility section below for more details.

none

Turns off the display of an element so that it has no effect on layout (the document is rendered as though the element did not exist). All descendant elements also have their display turned off. To have an element take up the space that it would normally take, but without actually rendering anything, use the visibility property instead.

Current implementations in most browsers will remove from the accessibility tree any element with a display value of contents. This will cause the element — and in some browser versions, its descendant elements — to no longer be announced by screen reading technology. This is incorrect behavior according to the CSSWG specification.

• More accessible markup with display: contents | Hidde de Vries
• Display: Contents Is Not a CSS Reset | Adrian Roselli

 = 
  contents  |
  none      

In this first example, the paragraph with a class of secret is set to display: none; the box and any content is now not rendered.

HTML

Visible text
Invisible text

CSS

p.secret {
  display: none;
}

Result

In this example the outer

  
Inner div.

.outer {
  border: 2px solid red;
  width: 300px;
  display: contents;
}

.outer > div {
  border: 1px solid green;
}

• display

• Display: Contents Is Not a CSS Reset | Adrian Roselli

• More accessible markup with display: contents by Hidde de Vries (2018)