Bugzilla – Bug 16429
Ensure that non-rectangular grid-template regions are explicitly called out as forbidden in the grid layout spec
Last modified: 2012-04-26 20:34:53 UTC
See this thread for more on this issue:
Assigning all Grid bugs to Phil Cupp.
Fixed in Section 6.6 of the April 20, 2012 Editor's Draft: http://dev.w3.org/csswg/css3-grid-layout/