[Meaning] Indicates that the property/element is understood, but that not all values are supported. Supported values are implemented correctly. [Value] 
Partial
Y e s
N o
P a r t i a l
I n c o r r e c t
E x p e r i m e n t a l
D r o p p e d
N i g h t l y b u i l d
D e p e n d s