Describe the bug:
The input a \mathrel{\vcenter{:}}= b produces the following markup:
<span class="katex"><span class="katex-mathml"><math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>a</mi><mo><mpadded class ="vcenter"><mo lspace="0em" rspace="0em">:</mo></mpadded></mo><mo>=</mo><mi>b</mi></mrow><annotation encoding="application/x-tex">a \mathrel{\vcenter{:}}= b</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.4653em;"></span><span class="mord mathnormal">a</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.4653em;"><span style="top:-3.0347em;"><span class="pstrut" style="height:3em;"></span><span class="mord"><span class="mrel">:</span></span></span></span></span></span></span></span><span class="base"><span class="strut" style="height:0.3669em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:0.6944em;"></span><span class="mord mathnormal">b</span></span></span></span>
Note the <mo><mpadded class ="vcenter">…</mo></mpadded> at the start. As https://validator.w3.org/nu/ informs me,
Error: Element mpadded not allowed as child of element mo in this context.
However, it doesn't give a link to the MathML specs where this is stated.
To Reproduce:
I used the following script to generate the markup:
import { createInterface } from "node:readline"
import { createRequire } from "module";
const katex = createRequire(import.meta.url)('katex');
for await (const line of createInterface({ input: process.stdin })) {
try {
console.log(katex.renderToString(line, {
displayMode: false,
strict: "error",
throwOnError: true,
}));
} catch (error) {
throw new Error(`Input: ${line}\n\nError: ${error}`);
}
}and then checked the output via https://validator.w3.org/nu/#textarea
Environment (please complete the following information):
- KaTeX Version: 0.16.21
- Device: Desktop
- OS: NixOS
- Browser: n/a
- Version: n/a
This seems related, but not completely identical, to Using underset does not render valid MathML #3978
Describe the bug:
The input
a \mathrel{\vcenter{:}}= bproduces the following markup:Note the
<mo><mpadded class ="vcenter">…</mo></mpadded>at the start. As https://validator.w3.org/nu/ informs me,However, it doesn't give a link to the MathML specs where this is stated.
To Reproduce:
I used the following script to generate the markup:
and then checked the output via https://validator.w3.org/nu/#textarea
Environment (please complete the following information):