This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
|Applies to||non-replaced elements|
|Computed value||as specified|
Default. No container has been specified.
The name of the region container.
[ none | <custom-ident> ]#
Not part of any specification.