Spec for the <div align> and <center> elements doesn't match reality.

[emilio]

What is the issue with the HTML Standard?

https://html.spec.whatwg.org/#flow-content-3:attr-div-align says to set text-align to center/left/right, and then do magic centering.

However, that doesn't match implementations, see w3c/csswg-drafts#10388.

Assuming w3c/csswg-drafts#10388 decides to specify this using the -webkit- prefixed keywords, would people be fine just mapping to that (matching reality)?

[Loirooriol]

CSS Align added justify-items: legacy precisely to explain this behavior. So once browser implement that, the mapping should be

• <center> and <div align="center"> into justify-items: legacy center; text-align: center
• <div align="left"> into justify-items: legacy left; text-align: left
• <div align="right"> into justify-items: legacy right; text-align: right

[annevk]

There's also #10149 and #3428? This should prolly be duplicated?