LaTeX/KaTeX rendering issue for PDF exports only

[lettersforword365]

I was testing out Marp and tried some LaTeX code for mathematical formulae.

I found that sigma notation does not seem to render correctly in PDF exports:

PDF Export:

HTML/PPTX Export:

I am running Marp for VS Code v1.5.2 on VS Code 1.70.1; device is on Windows 11 22H2.
The code for the formula I am using is:

# Some $\LaTeX$ Code

<br>

$$
\sum_{k=1}^{n}k^2 = \frac{n(n+1)(2n+1)}{6}
$$

This appears to be the case when I have not declared the math typesetting, or if it is declared as katex.

This is not the case when math typesetting is declared as mathjax, which is odd, as this says mathjax is used in rendering if there is no declaration (there is also a stylistic difference in rendering; no declaration appears to be using katex.)

PDF using MathJax:

I prefer usage of katex. Is there any "quick fix" for this, or a way in which different rendering engines could be used for different parts of the same equation?

[yhatt]

It seems to reproduce only in Chrome if exported to HTML. Firefox and Safari does not reproduce. (Marp's PDF export is depending on Chrome)

Marp has applied auto-shrink the size to KaTeX block, and it may be a one of incompatible parts with the auto scaling feature, as same as marp-team/marp-core#159 and marp-team/marp-core#236.

Workaround

Add following global style in Markdown.

<style>
  .katex .delimcenter,
  .katex .op-symbol {
    display: inline-block;
  }
</style>

If this workaround is working well, going to consider to add into KaTeX default style by Marp Core.

[yhatt]

This appears to be the case when I have not declared the math typesetting, or if it is declared as katex.

This is not the case when math typesetting is declared as mathjax, which is odd, as this says mathjax is used in rendering if there is no declaration (there is also a stylistic difference in rendering; no declaration appears to be using katex.)

In Marp for VS Code, use the library preferred in the extension settings if not defined math directive. You says "I prefer usage of katex" so you may be setting markdown.marp.mathTypesetting as katex. In this case, it's expected behavior that uses KaTeX when there is not set math directive.

[lettersforword365]

you may be setting markdown.marp.mathTypesetting as katex

just had a look at extension settings; looks like that is the default.

the workaround seems to work well for me as well; thanks for that!