[CSS21] In which block formatting context do things participate? (Was: Re: [CSS21] Proposal to define "Block container element")

Regarding a proposed addition to 9.2.1 (Block-level elements and block 
boxes),

On 25/07/2012 08:23, fantasai wrote:
>  | Unless a block box `establishes a new formatting context`_,
>  | its contents participate its containing block formatting context.
>
> [The proposed addition] fixes a missing idea that's already clear wrt
> inline boxes. Though
>    "participate in its containing block formatting context"
> is a little awkward, given we have the term "containing block". It's
> meant to parallel the similar statement in 9.2.2. We could replace both
> with
>    "participate in the same XXX formatting context as the XXX box itself"
> to be clearer.

Yes, the spec fails to say that each block-level box participates in its 
*closest ancestor* block formatting context.

I'm not sure about using "its contents participate" though.  Any 
inline-level children participate in the inline formatting context that 
the block box establishes, not in the ancestor block formatting context.

I think using "its block-level contents participate" is enough to fix that.

Cheers,
Anton Prowse
http://dev.moonhenge.net