Do you want to know how the CSS WG works? Fantasai has written about:csswg, An Inside View of the CSS Working Group at W3C.
:hoverto apply to an element because its child is designated by a pointing device, then it’s possible for
:hoverto apply to an element that is not underneath the pointing device. Rationale: The spec leaves undefined whether the
:hoverstate is passed up the DOM tree. Browsers all treat it that way and websites would break if that were changed. We’re adding this note to clarify to readers that it
:hovercan match an element even if it not hovered over if its child is positioned outside its geometric bounds.
:active, but made no resolutions about it.
an+bgrammar in ISSUE-66 to the Selectors spec.
The portion of a child element that occurs on the first
line inherits properties applicable to the ::first-line pseudo element; for properties not applicable to the ::first-line pseudo element, the inheritence is from the non-pseudo-element parent of the ::first-line pseudo element. The portion of a child element that does not occur on the first line always inherits from the parent of that child.