malformated table in revealjs when long equation with $\sqrt$ is used

[ThePurox]

I have:

• searched the issue tracker for similar issues
• installed the latest version of Quarto CLI
• formatted my issue following the Bug Reports guide

Bug description

The horizontal line in table on the slide broken is to long (see purple mark in screenshots below). From my testing the bug seems to appear, when a $\sqrt$ is in a long equation in the table. Short equations with $\sqrt$s are fine (see slide fine), so are long equations without $\sqrt$s are fine (see slide also fine).

Steps to reproduce

---
# render slides with $ quarto render slides.qmd
title: "broken table"
format:
  revealjs
---

## broken
| $M-N = 0$ | $M-N=1$ | $M-N \geq 2$ |
|-----------|---------|---------------|
| $v\propto \sqrt{a\rho D/c_{th}}$ | $v\propto a\rho / c_{th}$ | no waves|

## fine
| $M-N = 0$ | $M-N=1$ | $M-N \geq 2$ |
|-----------|---------|---------------|
| $v\propto \sqrt{a\rho D/c_t}$ | $v\propto a\rho / c_{th}$ | no waves|

## also fine
| $M-N = 0$ | $M-N=1$ | $M-N \geq 2$ |
|-----------|---------|---------------|
| $v\propto a\rho D/c_{trsthrsthrsth}$ | $v\propto a\rho / c_{th}$ | no waves|

Actual behavior

The horizontal line extends too far.

Expected behavior

The line should end shorty after the end of the text, as in the other slides

Your environment

Tested on Ubuntu 25.04 and Arch updated (2025-10-01)

Quarto check output

On arch machine:

quarto check
Quarto 1.8.25
[✓] Checking environment information...
      Quarto cache location: /home/nex/.cache/quarto
[✓] Checking versions of quarto binary dependencies...
      Pandoc version 3.6.3: OK
      Dart Sass version 1.87.0: OK
      Deno version 2.3.1: OK
      Typst version 0.13.0: OK
[✓] Checking versions of quarto dependencies......OK
[✓] Checking Quarto installation......OK
      Version: 1.8.25
      Path: /opt/quarto/bin

[✓] Checking tools....................OK
      TinyTeX: (not installed)
      Chromium: (not installed)

[✓] Checking LaTeX....................OK
      Using: Installation From Path
      Path: /usr/bin
      Version: undefined

[✓] Checking Chrome Headless....................OK
      Chrome:  (not detected)

[✓] Checking basic markdown render....OK

[✓] Checking Python 3 installation....OK
      Version: 3.13.7
      Path: /usr/bin/python3
      Jupyter: (None)

      Jupyter is not available in this Python installation.
      Install with python3 -m pip install jupyter

      There is an unactivated Python environment in systemd-private-08ea1f4900c6498f96cbc5f24ca384da-upower.service-opK2Pb. Did you forget to activate it?

[✓] Checking R installation...........(None)

      Unable to locate an installed version of R.
      Install R from https://cloud.r-project.org/

on ubuntu machine:

quarto check
Quarto 1.4.550
[✓] Checking versions of quarto binary dependencies...
      Pandoc version 3.1.11: OK
      Dart Sass version 1.69.5: OK
      Deno version 1.37.2: OK
[✓] Checking versions of quarto dependencies......OK
[✓] Checking Quarto installation......OK
      Version: 1.4.550
      Path: /opt/quarto/bin

[✓] Checking tools....................OK
      TinyTeX: (not installed)
      Chromium: (not installed)

[✓] Checking LaTeX....................OK
      Using: Installation From Path
      Path: /usr/bin
      Version: 2025

[✓] Checking basic markdown render....OK

[✓] Checking Python 3 installation....OK
      Version: 3.13.3
      Path: /usr/bin/python3
      Jupyter: (None)

      Jupyter is not available in this Python installation.
      Install with python3 -m pip install jupyter

[✓] Checking R installation...........(None)

      Unable to locate an installed version of R.
      Install R from https://cloud.r-project.org/

[mcanouil]

Accessibility: To improve accessibility, please add alternative text to your screenshots. This helps all users, including those using screen readers, to understand the context of the images. A brief description can make a big difference! See Good Alt Text, Bad Alt Text — Making Your Content Perceivable.

---

Your "also fine" slide is as "bad" as your "broken" slide on my end using latest Quarto CLI.

The issue is likely that you are using dynamic content inside a simple table, as the equations are rendered/displayed by your browser.
Reveal.js is also not using the latest version of MathJax which could be part of the styling issue.

You can get a more consistent style using grid-table instead of simple markdown table:

---
title: "broken table"
format: revealjs
---

## broken

+----------------------------------+---------------------------+----------------+
| $M-N = 0$                        | $M-N=1$                   | $M-N \geq 2$   |
+==================================+===========================+================+
| $v\propto \sqrt{a\rho D/c_{th}}$ | $v\propto a\rho / c_{th}$ | no waves       |
+----------------------------------+---------------------------+----------------+

## fine

+----------------------------------+---------------------------+----------------+
| $M-N = 0$                        | $M-N=1$                   | $M-N \geq 2$   |
+==================================+===========================+================+
| $v\propto \sqrt{a\rho D/c_t}$    | $v\propto a\rho / c_{th}$ | no waves       |
+----------------------------------+---------------------------+----------------+

## also fine

+--------------------------------------+---------------------------+----------------+
| $M-N = 0$                            | $M-N=1$                   | $M-N \geq 2$   |
+======================================+===========================+================+
| $v\propto a\rho D/c_{trsthrsthrsth}$ | $v\propto a\rho / c_{th}$ | no waves       |
+--------------------------------------+---------------------------+----------------+

See https://quarto.org/docs/authoring/tables.html#grid-tables

[ThePurox]

I've added alt texts, thanks for the reminder.
The grid-tables fix the issue on my side, thank you!

[mcanouil]

FYI, there is an extension that ease the creation of complex content for tables: https://github.com/pandoc-ext/list-table

(The grid-table syntax from Pandoc might exhibit some issues in some cases)