Allowing autoplay in data-background-iframe for audio and video elements

Add forgotten element to Table of Contents

Add mobileViewDistance config key

update minimal nodejs version in readme

Tweak to MathJax example

Update package.json for node 12 support

docs: fix typo

simple node-sass update which fixes this issue

Added a missing comma and used an actual macro so that the MathJax example runs right out of the box upon a copy/paste.

Fix plugin documentation regarding init-Promises

add missing comma to MathJax example in README

It was restricted by «Autoplay Policy Changes»: https://developers.google.com/web/updates/2017/09/autoplay-policy-changes#iframe

Fix arrow down navigation on touch devices

When using the totalTime-based pacing calculation, a presenter may
inadvertently set totalTime and per-slide data-timing attributes in
such a way that the pacing time for some slides is impossibly low or
even negative.

Add a check to ensure that the pacing on a slide never falls below a
configurable minimum, defaulting to 0. Display an alert if the
pacing for any slide(s) falls below the threshold.

new API methods for getting horizontal/vertical slides, force linear navigation for one-dimensional decks

iframe background preload behavior now matches inline iframes + adheres to the new 'preloadIframes' config option

The current pacing timer operates on the assumption that there is
a default amount of time to be allocated to each slide, and that
individual slides can deviate from that default by specifying their
own data-timing attribute.

This patch introduces an alternate pacing method: by specifying
the totalTime configuration option, the presenter can set the total
time available to present. The pacing timer will then continue to
allocate the exact pacing time for slides that do have data-timing
set, as before. However, rather than applying the defaultTiming
constant to all others, it will

- Add up the time already allocated to slides via data-timing;
- subtract that from totalTime;
- divide the difference by the number of slides without data-timing set;
- apply the thus-calculated average to those slides.

totalTime has no default, and if both defaultTiming and totalTime are
set, totalTime wins. This preserves backward compatibility: if a
presenter has set defaultTiming and updates reveal.js, totalTime will
be null and defaultTiming is still applied to all slides without a
data-timing attribute. The presenter can then switch to the automatic
calculation, if desired, by setting a value for totalTime.