[css-inline] Did root inline boxes become useless?

[Loirooriol]

I think the root inline box was only useful to explain the styling of text directly contained in a block container. But in #1118 (comment) the WG resolved that text runs have their own styles, they no longer need a box.

So I think that, as currently defined, root inline boxes became useless, and can be removed. Is that so?

If I'm right don't remove them yet, I have some alternative ideas for them.

[dbaron]

I think that the root inline box has a computed line-height property still helps explain how calculating the height of lines works, and possibly also vertical alignment.

[dbaron]

(... which is actually why the concept was added in the first place)

[Loirooriol]

I think that the root inline box has a computed line-height property still helps explain how calculating the height of lines works

Do you meant the strut? So now line-height applies only to inline boxes, but the root inline box inherits it from the block container, effectively replacing the following CSS2.1 quote?

On a block container element whose content is composed of inline-level elements, 'line-height' specifies the minimal height of line boxes within the element.

If so, this should be explained somewhere.

[fantasai]

@Loirooriol The relevant portions of https://drafts.csswg.org/css-inline-3/ are now filled out. Please have a look and let me know if you're OK to close this issue. :)

[Loirooriol]

Looks fine. But note that replacing the strut of the block container with the root inline box makes it less clear what should happen if there is ::first-line {line-height: 0}, because of #1384. See this non-interoperable testcase: https://bug1427241.bmoattachments.org/attachment.cgi?id=8939352