Bug 276360 – Remove legacy padding/margin rules from MathML UA stylesheet

• Status: RESOLVED
• Resolution: FIXED
• Component: MathML

[Frédéric Wang (:fredw)]

There are legacy rules that were used in earlier MathML implementations, for fine-tuning rendering or something, but they are arbitrary and not aligned with the MathML Core spec:

mi {
    padding-inline-end: 0.1em;
}
msub > mi:first-child, msubsup > mi:first-child {
    padding-inline-end: 0;
}
msubsup > mi:first-child + * + * {
    margin-inline-start: 0.14em; /* This is larger than 0.1em because the child's font-size is smaller than the <msubsup>'s. */
}

These are making mi tests for padding-002.html fail.

[Frédéric Wang (:fredw)]

Pull request: https://github.com/WebKit/WebKit/pull/30599

[EWS]

Committed 280785@main (a80eb4d127b1): <https://commits.webkit.org/280785@main>

Reviewed commits have been landed. Closing PR #30599 and removing active labels.

[Radar WebKit Bug Importer]

<rdar://problem/131399293>