Error in force(expr) : Failed to generate output in 30 seconds (timeout).

Hello!

I try to render a simple xaringan presentation:

---
title: "Example"
output: 
  xaringan::moon_reader:
    mathjax: "https://cdn.bootcss.com/mathjax/2.7.1/MathJax.js?config=TeX-MML-AM_HTMLorMML"
---

# Introduction

with the this code:

renderthis::to_pdf(from = "example.Rmd",
                   to = "example.pdf")

but I keep receiving an error:

(¬_¬)renderthis::to_pdf(from = "example.Rmd",
...                    to = "example.pdf")
✔ Rendering example.Rmd into example.html ... done
✖ Rendering example.html into example.pdf ... failed
Error in force(expr) : Failed to generate output in 30 seconds (timeout).

However, if I remove:

    mathjax: "https://cdn.bootcss.com/mathjax/2.7.1/MathJax.js?config=TeX-MML-AM_HTMLorMML"

it works:

(¬_¬)renderthis::to_pdf(from = "example.Rmd",
...                    to = "example.pdf")
✔ Rendering example.Rmd into example.html ... done
✔ Rendering example.html into example.pdf ... done

Reproduce the failure by running renderthis::to_pdf(from = "example.Rmd", to = "example.pdf") with the xaringan::moon_reader MathJax URL, then compare it with the working version without that setting. Done means example.Rmd renders to example.pdf successfully while retaining the configured MathJax URL.