Do you want to know how the CSS WG works? Fantasai has written about:csswg, An Inside View of the CSS Working Group at W3C.
Arron presented a draft for CSS3 Positioning, which includes CSS2.1 absolute, fixed, and relative positioning, containing blocks, and z-index; and that adds:
autooffsets compute to center the element within its containing block.
There were concerns raised that the page positioning scheme being proposed would result in layouts that broke very badly if the document were either rendered onto continuous (scrolling) canvas, or if it were paginated differently than the author’s original intent (due to differently-sized fonts, differently-sized pages, etc.). Thus:
Resolved: Publish CSS3 Positioning as FPWD, without
allis allowed within lists in
noneis not). Which item wins works like for shorthands, so it’s silly to use
allother than at the start of the list, but it’s not forbidden.