[css-content-3] content: none does not work as universally as the spec claims it does. #12998
Description
Currently, the none value of the content property says that:
On pseudo-elements it inhibits the creation of the pseudo-element as if it had display: none.
This is not respected universally in all three major browsers for all pseudo-elements. For example:
<!DOCTYPE html>
<style>
dialog::backdrop {
background-color: green;
content: none;
}
</style>
<dialog id="dialog"></dialog>
<script>
dialog.showModal();
</script>The green backdrop is visible in Firefox, Chrome and Safari.
I don't have time to test all the other pseudo-elements, but I'd assume that this is not just a problem with ::backdrop.