Bug 262696 – Align UA Stylesheet by adding default properties of 'semantics' and 'maction' section in mathml.css

• Component: MathML
• Status: NEW

[Ahmad Saleem]

SSIA.

We already have this partially but add two more rules:

/* <mrow>-like elements */
semantics > :not(:first-child) {
  display: none;
}

maction > :not(:first-child) {
  display: none;
}
merror {
  border: 1px solid red;
  background-color: lightYellow;
}
mphantom {
  visibility: hidden;
}

___

We already have last two so it is just re-arranging and adding first two.

Thanks!

[Ahmad Saleem]

I will do drive-by fixes and added section comments in this as well to make it easier to do few more follow-up alignments. :-)

[Radar WebKit Bug Importer]

<rdar://problem/116858835>

[Ahmad Saleem]

C++ Implementation needs to be removed as well beside this change - https://github.com/WebKit/WebKit/pull/18758

[Frédéric Wang (:fredw)]

(In reply to Ahmad Saleem from comment #3)
> C++ Implementation needs to be removed as well beside this change -
> https://github.com/WebKit/WebKit/pull/18758

Maybe this bug can thus be retitled, so that it's about aligning semantics/maction's implementation with MathML Core.

[Frédéric Wang (:fredw)]

From MathML Core, I see maction/semantics are grouping elements here: https://w3c.github.io/mathml-core/#dfn-grouping-elements and that they are laid out using the mrow algorithm. So probably we should just use the mrow element/renderer classes and add the corresponding CSS.

(We might want to experiment this change under a runtime flag)

[Ahmad Saleem]

(In reply to Frédéric Wang (:fredw) from comment #5)
> From MathML Core, I see maction/semantics are grouping elements here:
> https://w3c.github.io/mathml-core/#dfn-grouping-elements and that they are
> laid out using the mrow algorithm. So probably we should just use the mrow
> element/renderer classes and add the corresponding CSS.
> 
> (We might want to experiment this change under a runtime flag)

Should I retitle above PR and land it and then when we start implementing, we can add `C++` side behind flag?