\underbrace{}_{} error when rendering PDF

[XinyanYang95]

The underbrace is rendered weirdly in PDF. But this works for HTML.

$$
\underbrace{\phi+3}_{M}
$$

  pdf:
    documentclass: book
    keep-tex: true
    include-in-header: 
      - symboldefinitionspdf.tex
      - text: \usepackage{mathtools}

[mcanouil]

Could you share a small "working" (reproducible) example to work with, i.e., a complete Quarto document or a Git repository? Thanks.

You can share a Quarto document using the following syntax, i.e., using more backticks than you have in your document (usually four ````).

````qmd
---
title: "Reproducible Quarto Document"
format: html
---

This is a reproducible Quarto document using `format: html`.
It is written in Markdown and contains embedded R code.
When you run the code, it will produce a plot.

```{r}
plot(cars)
```

The end.
````

[cscheid]

The reason we're somewhat insistent on asking for full files is that we need to be able to render your example exactly as you see it. The snippet you shared has a YAML syntax error. In addition, it works for me when I add a colon to the pdf line:

[XinyanYang95]

Oh, I have the colon after pdf in my _quarto.yml file. I forgot it here. Sorry for the confusion.

But when I rendered my file with VS code using "quarto render -t pdf", the underbraces are not printed out correctly.

[cscheid]

_quarto.yml

You didn't share a _quarto.yml file. You shared a single .qmd file. I will repeat: it's very important that you provide output from the actual example you ran. And, when you run the example you gave, the output is fine:

$ cat 5564.qmd
---
title: "Test"
format:
    pdf:
        keep-tex: true
        include-in-header:
            - text: \usepackage{mathtools}
---

$$
\underbrace{\phi+3}_{M}
$$

$ quarto render 5564.qmd --to pdf
pandoc
  to: latex
  output-file: 5564.tex
  standalone: true
  pdf-engine: xelatex
  variables:
    graphics: true
    tables: true
  default-image-extension: pdf

metadata
  documentclass: scrartcl
  classoption:
    - DIV=11
    - numbers=noendperiod
  papersize: letter
  header-includes:
    - '\KOMAoption{captions}{tableheading}'
  block-headings: true
  title: Test

running xelatex - 1
  This is XeTeX, Version 3.141592653-2.6-0.999995 (TeX Live 2023) (preloaded format=xelatex)
   restricted \write18 enabled.
  entering extended mode

running xelatex - 2
  This is XeTeX, Version 3.141592653-2.6-0.999995 (TeX Live 2023) (preloaded format=xelatex)
   restricted \write18 enabled.
  entering extended mode


Output created: 5564.pdf

So, please do make a concerted effort to provide the actual example that you are using to claim there's a problem. It's hard for us to diagnose the issue otherwise.

[XinyanYang95]

I found this is a font problem. For "fontfamily: libertinus", underbraces cannot be printed out.

[mcanouil]

Thus the importance of providing fully and complete reproducible example.