I filed this as:
https://github.com/w3c/fxtf-drafts/issues/3
but it doesn't look like github issues are mailed to this list (like they are
for other specs) so I'm sending this email too.
--
https://drafts.csswg.org/css-shapes-1/#basic-shape-serialization
specifies how basic shapes should be serialized. However, a clip-path value can
also contain a <geometry-box> and nothing seems to specify how clip-path as a
whole serializes.
Since the text for basic shape serialization says something like "if part of the
value is a default value and omitting it won't affect the result, omit it", it
would seem on the surface to make sense to do that for clip-path as a whole too.
That would seem to imply that if a shape and the default value for
<geometry-box> of border-box is specified, the serialization would just be the
shape. If however just a <geometry-box> is specified its value would need to be
serialized regardless of whether it is the default or not.
That said, Mozilla's implementation would not make it very easy to skip
serialization of the <geometry-box> since, at the point in the code where we
serialize the enum, we don't have any information about whether the enum value
is paired with a shape.
