text inflation in mobile browser

[gwmatthews]

Problem

Due to a "feature" in some mobile phone browsers, font sizes get inflated in certain circumstances when viewing slides. This can cause overflow of slide content off of readable screen area. This affects the right-column class and possibly user-defined classes as well. Yes that's native to remark, but this is intended as a fix for the internal themes here.

When displaying slideshow on Android Chrome text within right-column class gets inflated.

Text in right-column class

Normal text

Fix

I struggled with fixing this until I found the option to disable text size adjustments, which is a newish css property. So I thought I'd recommend adding it to css files lest mobile viewers can't read your slideshows. Adding the css rule below maintains consistent text sizes.

/*   prevent small screen font size inflation */

body {
  -webkit-text-size-adjust: none;
  -moz-text-size-adjust: none;
  -ms-text-size-adjust: none;
}

Here's a minimal working example. To reproduce:

1. knit
2. deploy to web
3. view in Android Chrome

---
title: "test"
author: "me"
output:
  xaringan::moon_reader:
    seal: false
    lib_dir: libs
    nature:
      highlightStyle: github
      countIncrementalSlides: false
---

# inflated text

.left-column[

### heading

]

.right-column[

Twas brillig, and the slithy toves
      
Did gyre and gimble in the wabe:

All mimsy were the borogoves,

And the mome raths outgrabe.

"Beware the Jabberwock, my son!

The jaws that bite, the claws that catch!

Beware the Jubjub bird, and shun

The frumious Bandersnatch!"

]

---

# non-inflated text

Twas brillig, and the slithy toves
      
Did gyre and gimble in the wabe:

All mimsy were the borogoves,

And the mome raths outgrabe.

"Beware the Jabberwock, my son!

The jaws that bite, the claws that catch!

Beware the Jubjub bird, and shun

The frumious Bandersnatch!"

---

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