Maintained matrix of CSS properties v. browsers/rendering engines ?

Is there a maintained matrix shewing CSS properties and
the degree to which each of the major browsers / rendering
engines handle them ?   I ask because my experiments
suggest that Seamonkey (a Mozilla/Gecko-derivative) copes
reasonably well with "page-break-before: always", but seems
unable to cope with either "page-break-after: avoid" or
"page-break-inside: avoid".

Philip Taylor