Math newline with default MathJax not working

[retodomax]

I'm trying to switch from RMarkdown to Quarto and something which gives me some problem is to create newlines in display math. Reprex:

---
title: Math newline with Quarto
format:
  html
---

# Equation

$$
x = 1 \\
y = 2
$$

Seems to be a problem with Mathjax but why does it work in RMarkdown? Maybe another version of MathJax was used? Is is possible to select the same version of MathJax used in RMarkdown?

[cderv]

R Markdown ecosystem use Mathjax 2 by default. Not yet upgrade to Mathjax 3
See discussion at rstudio/bookdown#1364 (comment)

Default Mathjax in Quarto will be 3 - which unfortunately has this limitation.

But as explained in the documentation, you can change to what you want:
https://quarto.org/docs/output-formats/html-basics.html#latex-equations

---
title: Math newline with Quarto
format: 
  html:
    html-math-method:
      method: mathjax
      url: "https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.9/latest.js?config=TeX-MML-AM_CHTML"
---

# Equation

$$
x = 1 \\
y = 2
$$

You can use other math method too - see the doc

[cderv]

I published this as a an example for later reference to it https://examples.quarto.pub/changing-mathjax/