ox-reveal update

2022-04-25 18:47:51 +02:00
parent 2ff6f7e396
commit 2db1c0afe0
84 changed files with 15869 additions and 5383 deletions
--- a/scripts/reveal.js/js/config.js
+++ b/scripts/reveal.js/js/config.js
@@ -73,8 +73,8 @@ export default {

 	// Optional function that blocks keyboard events when retuning false
 	//
-	// If you set this to 'foucsed', we will only capture keyboard events
-	// for embdedded decks when they are in focus
+	// If you set this to 'focused', we will only capture keyboard events
+	// for embedded decks when they are in focus
 	keyboardCondition: null,

 	// Disables the default reveal.js slide layout (scaling and centering)
@@ -149,7 +149,7 @@ export default {
 	// Flags if slides with data-visibility="hidden" should be kep visible
 	showHiddenSlides: false,

-	// Global override for autolaying embedded media (video/audio/iframe)
+	// Global override for autoplaying embedded media (video/audio/iframe)
 	// - null:   Media will only autoplay if data-autoplay is present
 	// - true:   All media will autoplay, regardless of individual setting
 	// - false:  No media will autoplay, regardless of individual setting
--- a/scripts/reveal.js/js/controllers/autoanimate.js
+++ b/scripts/reveal.js/js/controllers/autoanimate.js
@@ -27,8 +27,16 @@ export default class AutoAnimate {
 		// Clean up after prior animations
 		this.reset();

-		// Ensure that both slides are auto-animate targets
-		if( fromSlide.hasAttribute( 'data-auto-animate' ) && toSlide.hasAttribute( 'data-auto-animate' ) ) {
+		let allSlides = this.Reveal.getSlides();
+		let toSlideIndex = allSlides.indexOf( toSlide );
+		let fromSlideIndex = allSlides.indexOf( fromSlide );
+
+		// Ensure that both slides are auto-animate targets with the same data-auto-animate-id value
+		// (including null if absent on both) and that data-auto-animate-restart isn't set on the
+		// physically latter slide (independent of slide direction)
+		if( fromSlide.hasAttribute( 'data-auto-animate' ) && toSlide.hasAttribute( 'data-auto-animate' )
+				&& fromSlide.getAttribute( 'data-auto-animate-id' ) === toSlide.getAttribute( 'data-auto-animate-id' ) 
+				&& !( toSlideIndex > fromSlideIndex ? toSlide : fromSlide ).hasAttribute( 'data-auto-animate-restart' ) ) {

 			// Create a new auto-animate sheet
 			this.autoAnimateStyleSheet = this.autoAnimateStyleSheet || createStyleSheet();
@@ -40,8 +48,7 @@ export default class AutoAnimate {
 			toSlide.dataset.autoAnimate = 'pending';

 			// Flag the navigation direction, needed for fragment buildup
-			let allSlides = this.Reveal.getSlides();
-			animationOptions.slideDirection = allSlides.indexOf( toSlide ) > allSlides.indexOf( fromSlide ) ? 'forward' : 'backward';
+			animationOptions.slideDirection = toSlideIndex > fromSlideIndex ? 'forward' : 'backward';

 			// Inject our auto-animate styles for this transition
 			let css = this.getAutoAnimatableElements( fromSlide, toSlide ).map( elements => {
--- a/scripts/reveal.js/js/controllers/backgrounds.js
+++ b/scripts/reveal.js/js/controllers/backgrounds.js
@@ -27,8 +27,6 @@ export default class Backgrounds {
 	 */
 	create() {

-		let printMode = this.Reveal.isPrintingPDF();
-
 		// Clear prior backgrounds
 		this.element.innerHTML = '';
 		this.element.classList.add( 'no-transition' );
@@ -114,9 +112,24 @@ export default class Backgrounds {
 	 */
 	sync( slide ) {

-		let element = slide.slideBackgroundElement,
+		const element = slide.slideBackgroundElement,
 			contentElement = slide.slideBackgroundContentElement;

+		const data = {
+			background: slide.getAttribute( 'data-background' ),
+			backgroundSize: slide.getAttribute( 'data-background-size' ),
+			backgroundImage: slide.getAttribute( 'data-background-image' ),
+			backgroundVideo: slide.getAttribute( 'data-background-video' ),
+			backgroundIframe: slide.getAttribute( 'data-background-iframe' ),
+			backgroundColor: slide.getAttribute( 'data-background-color' ),
+			backgroundRepeat: slide.getAttribute( 'data-background-repeat' ),
+			backgroundPosition: slide.getAttribute( 'data-background-position' ),
+			backgroundTransition: slide.getAttribute( 'data-background-transition' ),
+			backgroundOpacity: slide.getAttribute( 'data-background-opacity' ),
+		};
+
+		const dataPreload = slide.hasAttribute( 'data-preload' );
+
 		// Reset the prior background state in case this is not the
 		// initial sync
 		slide.classList.remove( 'has-dark-background' );
@@ -135,19 +148,6 @@ export default class Backgrounds {
 		contentElement.style.opacity = '';
 		contentElement.innerHTML = '';

-		let data = {
-			background: slide.getAttribute( 'data-background' ),
-			backgroundSize: slide.getAttribute( 'data-background-size' ),
-			backgroundImage: slide.getAttribute( 'data-background-image' ),
-			backgroundVideo: slide.getAttribute( 'data-background-video' ),
-			backgroundIframe: slide.getAttribute( 'data-background-iframe' ),
-			backgroundColor: slide.getAttribute( 'data-background-color' ),
-			backgroundRepeat: slide.getAttribute( 'data-background-repeat' ),
-			backgroundPosition: slide.getAttribute( 'data-background-position' ),
-			backgroundTransition: slide.getAttribute( 'data-background-transition' ),
-			backgroundOpacity: slide.getAttribute( 'data-background-opacity' )
-		};
-
 		if( data.background ) {
 			// Auto-wrap image urls in url(...)
 			if( /^(http|file|\/\/)/gi.test( data.background ) || /\.(svg|png|jpg|jpeg|gif|bmp)([?#\s]|$)/gi.test( data.background ) ) {
@@ -179,7 +179,7 @@ export default class Backgrounds {
 		if( data.backgroundColor ) element.style.backgroundColor = data.backgroundColor;
 		if( data.backgroundTransition ) element.setAttribute( 'data-background-transition', data.backgroundTransition );

-		if( slide.hasAttribute( 'data-preload' ) ) element.setAttribute( 'data-preload', '' );
+		if( dataPreload ) element.setAttribute( 'data-preload', '' );

 		// Background image options are set on the content wrapper
 		if( data.backgroundSize ) contentElement.style.backgroundSize = data.backgroundSize;
@@ -192,8 +192,8 @@ export default class Backgrounds {
 		// color, no class will be added
 		let contrastColor = data.backgroundColor;

-		// If no bg color was found, check the computed background
-		if( !contrastColor ) {
+		// If no bg color was found, or it cannot be converted by colorToRgb, check the computed background
+		if( !contrastColor || !colorToRgb( contrastColor ) ) {
 			let computedBackgroundStyle = window.getComputedStyle( element );
 			if( computedBackgroundStyle && computedBackgroundStyle.backgroundColor ) {
 				contrastColor = computedBackgroundStyle.backgroundColor;
@@ -201,7 +201,7 @@ export default class Backgrounds {
 		}

 		if( contrastColor ) {
-			let rgb = colorToRgb( contrastColor );
+			const rgb = colorToRgb( contrastColor );

 			// Ignore fully transparent backgrounds. Some browsers return
 			// rgba(0,0,0,0) when reading the computed background color of
@@ -394,4 +394,10 @@ export default class Backgrounds {

 	}

-}
+	destroy() {
+
+		this.element.remove();
+
+	}
+
+}
--- a/scripts/reveal.js/js/controllers/controls.js
+++ b/scripts/reveal.js/js/controllers/controls.js
@@ -188,6 +188,13 @@ export default class Controls {
 		}
 	}

+	destroy() {
+
+		this.unbind();
+		this.element.remove();
+
+	}
+
 	/**
 	 * Event handlers for navigation control buttons.
 	 */
--- a/scripts/reveal.js/js/controllers/focus.js
+++ b/scripts/reveal.js/js/controllers/focus.js
@@ -79,6 +79,12 @@ export default class Focus {

 	}

+	destroy() {
+
+		this.Reveal.getRevealElement().classList.remove( 'focused' );
+
+	}
+
 	onRevealPointerDown( event ) {

 		this.focus();
--- a/scripts/reveal.js/js/controllers/fragments.js
+++ b/scripts/reveal.js/js/controllers/fragments.js
@@ -235,6 +235,7 @@ export default class Fragments {
 						el.classList.remove( 'current-fragment' );

 						if( wasVisible ) {
+							this.Reveal.slideContent.stopEmbeddedContent( el );
 							changedFragments.hidden.push( el );
 							this.Reveal.dispatchEvent({
 								target: el,
--- a/scripts/reveal.js/js/controllers/keyboard.js
+++ b/scripts/reveal.js/js/controllers/keyboard.js
@@ -32,15 +32,15 @@ export default class Keyboard {
 		}
 		else {
 			this.shortcuts['N  ,  SPACE']   = 'Next slide';
-			this.shortcuts['P']             = 'Previous slide';
+			this.shortcuts['P  ,  Shift SPACE']             = 'Previous slide';
 			this.shortcuts['&#8592;  ,  H'] = 'Navigate left';
 			this.shortcuts['&#8594;  ,  L'] = 'Navigate right';
 			this.shortcuts['&#8593;  ,  K'] = 'Navigate up';
 			this.shortcuts['&#8595;  ,  J'] = 'Navigate down';
 		}

-		this.shortcuts['Home  ,  Shift &#8592;']        = 'First slide';
-		this.shortcuts['End  ,  Shift &#8594;']         = 'Last slide';
+		this.shortcuts['Alt + &#8592;/&#8593/&#8594;/&#8595;']        = 'Navigate without fragments';
+		this.shortcuts['Shift + &#8592;/&#8593/&#8594;/&#8595;']      = 'Jump to first/last slide';
 		this.shortcuts['B  ,  .']                       = 'Pause';
 		this.shortcuts['F']                             = 'Fullscreen';
 		this.shortcuts['ESC, O']                        = 'Slide overview';
@@ -182,13 +182,11 @@ export default class Keyboard {
 		let activeElementIsInput = document.activeElement && document.activeElement.tagName && /input|textarea/i.test( document.activeElement.tagName );
 		let activeElementIsNotes = document.activeElement && document.activeElement.className && /speaker-notes/i.test( document.activeElement.className);

-		// Whitelist specific modified + keycode combinations
-		let prevSlideShortcut = event.shiftKey && event.keyCode === 32;
-		let firstSlideShortcut = event.shiftKey && keyCode === 37;
-		let lastSlideShortcut = event.shiftKey && keyCode === 39;
+		// Whitelist certain modifiers for slide navigation shortcuts
+		let isNavigationKey = [32, 37, 38, 39, 40, 78, 80].indexOf( event.keyCode ) !== -1;

 		// Prevent all other events when a modifier is pressed
-		let unusedModifier = 	!prevSlideShortcut && !firstSlideShortcut && !lastSlideShortcut &&
+		let unusedModifier = 	!( isNavigationKey && event.shiftKey || event.altKey ) &&
 								( event.shiftKey || event.altKey || event.ctrlKey || event.metaKey );

 		// Disregard the event if there's a focused element or a
@@ -277,52 +275,58 @@ export default class Keyboard {

 			// P, PAGE UP
 			if( keyCode === 80 || keyCode === 33 ) {
-				this.Reveal.prev();
+				this.Reveal.prev({skipFragments: event.altKey});
 			}
 			// N, PAGE DOWN
 			else if( keyCode === 78 || keyCode === 34 ) {
-				this.Reveal.next();
+				this.Reveal.next({skipFragments: event.altKey});
 			}
 			// H, LEFT
 			else if( keyCode === 72 || keyCode === 37 ) {
-				if( firstSlideShortcut ) {
+				if( event.shiftKey ) {
 					this.Reveal.slide( 0 );
 				}
 				else if( !this.Reveal.overview.isActive() && useLinearMode ) {
-					this.Reveal.prev();
+					this.Reveal.prev({skipFragments: event.altKey});
 				}
 				else {
-					this.Reveal.left();
+					this.Reveal.left({skipFragments: event.altKey});
 				}
 			}
 			// L, RIGHT
 			else if( keyCode === 76 || keyCode === 39 ) {
-				if( lastSlideShortcut ) {
-					this.Reveal.slide( Number.MAX_VALUE );
+				if( event.shiftKey ) {
+					this.Reveal.slide( this.Reveal.getHorizontalSlides().length - 1 );
 				}
 				else if( !this.Reveal.overview.isActive() && useLinearMode ) {
-					this.Reveal.next();
+					this.Reveal.next({skipFragments: event.altKey});
 				}
 				else {
-					this.Reveal.right();
+					this.Reveal.right({skipFragments: event.altKey});
 				}
 			}
 			// K, UP
 			else if( keyCode === 75 || keyCode === 38 ) {
-				if( !this.Reveal.overview.isActive() && useLinearMode ) {
-					this.Reveal.prev();
+				if( event.shiftKey ) {
+					this.Reveal.slide( undefined, 0 );
+				}
+				else if( !this.Reveal.overview.isActive() && useLinearMode ) {
+					this.Reveal.prev({skipFragments: event.altKey});
 				}
 				else {
-					this.Reveal.up();
+					this.Reveal.up({skipFragments: event.altKey});
 				}
 			}
 			// J, DOWN
 			else if( keyCode === 74 || keyCode === 40 ) {
-				if( !this.Reveal.overview.isActive() && useLinearMode ) {
-					this.Reveal.next();
+				if( event.shiftKey ) {
+					this.Reveal.slide( undefined, Number.MAX_VALUE );
+				}
+				else if( !this.Reveal.overview.isActive() && useLinearMode ) {
+					this.Reveal.next({skipFragments: event.altKey});
 				}
 				else {
-					this.Reveal.down();
+					this.Reveal.down({skipFragments: event.altKey});
 				}
 			}
 			// HOME
@@ -331,7 +335,7 @@ export default class Keyboard {
 			}
 			// END
 			else if( keyCode === 35 ) {
-				this.Reveal.slide( Number.MAX_VALUE );
+				this.Reveal.slide( this.Reveal.getHorizontalSlides().length - 1 );
 			}
 			// SPACE
 			else if( keyCode === 32 ) {
@@ -339,10 +343,10 @@ export default class Keyboard {
 					this.Reveal.overview.deactivate();
 				}
 				if( event.shiftKey ) {
-					this.Reveal.prev();
+					this.Reveal.prev({skipFragments: event.altKey});
 				}
 				else {
-					this.Reveal.next();
+					this.Reveal.next({skipFragments: event.altKey});
 				}
 			}
 			// TWO-SPOT, SEMICOLON, B, V, PERIOD, LOGITECH PRESENTER TOOLS "BLACK SCREEN" BUTTON
--- a/scripts/reveal.js/js/controllers/location.js
+++ b/scripts/reveal.js/js/controllers/location.js
@@ -3,6 +3,10 @@
 */
 export default class Location {

+	// The minimum number of milliseconds that must pass between
+	// calls to history.replaceState
+	MAX_REPLACE_STATE_FREQUENCY = 1000
+
 	constructor( Reveal ) {

 		this.Reveal = Reveal;
@@ -10,6 +14,8 @@ export default class Location {
 		// Delays updates to the URL due to a Chrome thumbnailer bug
 		this.writeURLTimeout = 0;

+		this.replaceStateTimestamp = 0;
+
 		this.onWindowHashChange = this.onWindowHashChange.bind( this );

 	}
@@ -27,19 +33,18 @@ export default class Location {
 	}

 	/**
-	 * Reads the current URL (hash) and navigates accordingly.
+	 * Returns the slide indices for the given hash link.
+	 *
+	 * @param {string} [hash] the hash string that we want to
+	 * find the indices for
+	 *
+	 * @returns slide indices or null
 	 */
-	readURL() {
-
-		let config = this.Reveal.getConfig();
-		let indices = this.Reveal.getIndices();
-		let currentSlide = this.Reveal.getCurrentSlide();
-
-		let hash = window.location.hash;
+	getIndicesFromHash( hash=window.location.hash ) {

 		// Attempt to parse the hash as either an index or name
-		let bits = hash.slice( 2 ).split( '/' ),
-			name = hash.replace( /#\/?/gi, '' );
+		let name = hash.replace( /^#\/?/, '' );
+		let bits = name.split( '/' );

 		// If the first bit is not fully numeric and there is a name we
 		// can assume that this is a named link
@@ -61,23 +66,12 @@ export default class Location {
 			}
 			catch ( error ) { }

-			// Ensure that we're not already on a slide with the same name
-			let isSameNameAsCurrentSlide = currentSlide ? currentSlide.getAttribute( 'id' ) === name : false;
-
 			if( element ) {
-				// If the slide exists and is not the current slide...
-				if ( !isSameNameAsCurrentSlide || typeof f !== 'undefined' ) {
-					// ...find the position of the named slide and navigate to it
-					let slideIndices = this.Reveal.getIndices( element );
-					this.Reveal.slide( slideIndices.h, slideIndices.v, f );
-				}
-			}
-			// If the slide doesn't exist, navigate to the current slide
-			else {
-				this.Reveal.slide( indices.h || 0, indices.v || 0 );
+				return { ...this.Reveal.getIndices( element ), f };
 			}
 		}
 		else {
+			const config = this.Reveal.getConfig();
 			let hashIndexBase = config.hashOneBasedIndex ? 1 : 0;

 			// Read the index components of the hash
@@ -92,10 +86,32 @@ export default class Location {
 				}
 			}

-			if( h !== indices.h || v !== indices.v || f !== undefined ) {
-				this.Reveal.slide( h, v, f );
+			return { h, v, f };
+		}
+
+		// The hash couldn't be parsed or no matching named link was found
+		return null
+
+	}
+
+	/**
+	 * Reads the current URL (hash) and navigates accordingly.
+	 */
+	readURL() {
+
+		const currentIndices = this.Reveal.getIndices();
+		const newIndices = this.getIndicesFromHash();
+
+		if( newIndices ) {
+			if( ( newIndices.h !== currentIndices.h || newIndices.v !== currentIndices.v || newIndices.f !== undefined ) ) {
+					this.Reveal.slide( newIndices.h, newIndices.v, newIndices.f );
 			}
 		}
+		// If no new indices are available, we're trying to navigate to
+		// a slide hash that does not exist
+		else {
+			this.Reveal.slide( currentIndices.h || 0, currentIndices.v || 0 );
+		}

 	}

@@ -132,10 +148,10 @@ export default class Location {
 			else if( config.hash ) {
 				// If the hash is empty, don't add it to the URL
 				if( hash === '/' ) {
-					window.history.replaceState( null, null, window.location.pathname + window.location.search );
+					this.debouncedReplaceState( window.location.pathname + window.location.search );
 				}
 				else {
-					window.history.replaceState( null, null, '#' + hash );
+					this.debouncedReplaceState( '#' + hash );
 				}
 			}
 			// UPDATE: The below nuking of all hash changes breaks
@@ -153,6 +169,26 @@ export default class Location {

 	}

+	replaceState( url ) {
+
+		window.history.replaceState( null, null, url );
+		this.replaceStateTimestamp = Date.now();
+
+	}
+
+	debouncedReplaceState( url ) {
+
+		clearTimeout( this.replaceStateTimeout );
+
+		if( Date.now() - this.replaceStateTimestamp > this.MAX_REPLACE_STATE_FREQUENCY ) {
+			this.replaceState( url );
+		}
+		else {
+			this.replaceStateTimeout = setTimeout( () => this.replaceState( url ), this.MAX_REPLACE_STATE_FREQUENCY );
+		}
+
+	}
+
 	/**
 	 * Return a hash URL that will resolve to the given slide location.
 	 *
--- a/scripts/reveal.js/js/controllers/notes.js
+++ b/scripts/reveal.js/js/controllers/notes.js
@@ -111,4 +111,10 @@ export default class Notes {

 	}

+	destroy() {
+
+		this.element.remove();
+
+	}
+
 }
--- a/scripts/reveal.js/js/controllers/plugins.js
+++ b/scripts/reveal.js/js/controllers/plugins.js
@@ -238,4 +238,17 @@ export default class Plugins {

 	}

+	destroy() {
+
+		Object.values( this.registeredPlugins ).forEach( plugin => {
+			if( typeof plugin.destroy === 'function' ) {
+				plugin.destroy();
+			}
+		} );
+
+		this.registeredPlugins = {};
+		this.asyncDependencies = [];
+
+	}
+
 }
--- a/scripts/reveal.js/js/controllers/pointer.js
+++ b/scripts/reveal.js/js/controllers/pointer.js
@@ -75,6 +75,17 @@ export default class Pointer {

 	}

+	destroy() {
+
+		this.showCursor();
+
+		document.removeEventListener( 'DOMMouseScroll', this.onDocumentMouseScroll, false );
+		document.removeEventListener( 'mousewheel', this.onDocumentMouseScroll, false );
+		document.removeEventListener( 'mousemove', this.onDocumentCursorActive, false );
+		document.removeEventListener( 'mousedown', this.onDocumentCursorActive, false );
+
+	}
+
 	/**
 	 * Called whenever there is mouse input at the document level
 	 * to determine if the cursor is active or not.
--- a/scripts/reveal.js/js/controllers/print.js
+++ b/scripts/reveal.js/js/controllers/print.js
@@ -16,20 +16,26 @@ export default class Print {
 	 * Configures the presentation for printing to a static
 	 * PDF.
 	 */
-	setupPDF() {
+	async setupPDF() {

-		let config = this.Reveal.getConfig();
+		const config = this.Reveal.getConfig();
+		const slides = queryAll( this.Reveal.getRevealElement(), SLIDES_SELECTOR )

-		let slideSize = this.Reveal.getComputedSlideSize( window.innerWidth, window.innerHeight );
+		// Compute slide numbers now, before we start duplicating slides
+		const doingSlideNumbers = config.slideNumber && /all|print/i.test( config.showSlideNumber );
+
+		const slideSize = this.Reveal.getComputedSlideSize( window.innerWidth, window.innerHeight );

 		// Dimensions of the PDF pages
-		let pageWidth = Math.floor( slideSize.width * ( 1 + config.margin ) ),
+		const pageWidth = Math.floor( slideSize.width * ( 1 + config.margin ) ),
 			pageHeight = Math.floor( slideSize.height * ( 1 + config.margin ) );

 		// Dimensions of slides within the pages
-		let slideWidth = slideSize.width,
+		const slideWidth = slideSize.width,
 			slideHeight = slideSize.height;

+		await new Promise( requestAnimationFrame );
+
 		// Let the browser know what page size we want to print
 		createStyleSheet( '@page{size:'+ pageWidth +'px '+ pageHeight +'px; margin: 0px;}' );

@@ -40,26 +46,38 @@ export default class Print {
 		document.body.style.width = pageWidth + 'px';
 		document.body.style.height = pageHeight + 'px';

+		const viewportElement = document.querySelector( '.reveal-viewport' );
+		let presentationBackground;
+		if( viewportElement ) {
+			const viewportStyles = window.getComputedStyle( viewportElement );
+			if( viewportStyles && viewportStyles.background ) {
+				presentationBackground = viewportStyles.background;
+			}
+		}
+
 		// Make sure stretch elements fit on slide
+		await new Promise( requestAnimationFrame );
 		this.Reveal.layoutSlideContents( slideWidth, slideHeight );

-		// Compute slide numbers now, before we start duplicating slides
-		let doingSlideNumbers = config.slideNumber && /all|print/i.test( config.showSlideNumber );
-		queryAll( this.Reveal.getRevealElement(), SLIDES_SELECTOR ).forEach( function( slide ) {
-			slide.setAttribute( 'data-slide-number', this.Reveal.slideNumber.getSlideNumber( slide ) );
-		}, this );
+		// Batch scrollHeight access to prevent layout thrashing
+		await new Promise( requestAnimationFrame );
+
+		const slideScrollHeights = slides.map( slide => slide.scrollHeight );
+
+		const pages = [];
+		const pageContainer = slides[0].parentNode;

 		// Slide and slide background layout
-		queryAll( this.Reveal.getRevealElement(), SLIDES_SELECTOR ).forEach( function( slide ) {
+		slides.forEach( function( slide, index ) {

 			// Vertical stacks are not centred since their section
 			// children will be
 			if( slide.classList.contains( 'stack' ) === false ) {
 				// Center the slide inside of the page, giving the slide some margin
-				let left = ( pageWidth - slideWidth ) / 2,
-					top = ( pageHeight - slideHeight ) / 2;
+				let left = ( pageWidth - slideWidth ) / 2;
+				let top = ( pageHeight - slideHeight ) / 2;

-				let contentHeight = slide.scrollHeight;
+				const contentHeight = slideScrollHeights[ index ];
 				let numberOfPages = Math.max( Math.ceil( contentHeight / pageHeight ), 1 );

 				// Adhere to configured pages per slide limit
@@ -72,10 +90,18 @@ export default class Print {

 				// Wrap the slide in a page element and hide its overflow
 				// so that no page ever flows onto another
-				let page = document.createElement( 'div' );
+				const page = document.createElement( 'div' );
+				pages.push( page );
+
 				page.className = 'pdf-page';
 				page.style.height = ( ( pageHeight + config.pdfPageHeightOffset ) * numberOfPages ) + 'px';
-				slide.parentNode.insertBefore( page, slide );
+
+				// Copy the presentation-wide background to each individual
+				// page when printing
+				if( presentationBackground ) {
+					page.style.background = presentationBackground;
+				}
+
 				page.appendChild( slide );

 				// Position the slide inside of the page
@@ -83,6 +109,10 @@ export default class Print {
 				slide.style.top = top + 'px';
 				slide.style.width = slideWidth + 'px';

+				// Re-run the slide layout so that r-fit-text is applied based on
+				// the printed slide size
+				this.Reveal.slideContent.layout( slide )
+
 				if( slide.slideBackgroundElement ) {
 					page.insertBefore( slide.slideBackgroundElement, slide );
 				}
@@ -91,19 +121,19 @@ export default class Print {
 				if( config.showNotes ) {

 					// Are there notes for this slide?
-					let notes = this.Reveal.getSlideNotes( slide );
+					const notes = this.Reveal.getSlideNotes( slide );
 					if( notes ) {

-						let notesSpacing = 8;
-						let notesLayout = typeof config.showNotes === 'string' ? config.showNotes : 'inline';
-						let notesElement = document.createElement( 'div' );
+						const notesSpacing = 8;
+						const notesLayout = typeof config.showNotes === 'string' ? config.showNotes : 'inline';
+						const notesElement = document.createElement( 'div' );
 						notesElement.classList.add( 'speaker-notes' );
 						notesElement.classList.add( 'speaker-notes-pdf' );
 						notesElement.setAttribute( 'data-layout', notesLayout );
 						notesElement.innerHTML = notes;

 						if( notesLayout === 'separate-page' ) {
-							page.parentNode.insertBefore( notesElement, page.nextSibling );
+							pages.push( notesElement );
 						}
 						else {
 							notesElement.style.left = notesSpacing + 'px';
@@ -118,10 +148,11 @@ export default class Print {

 				// Inject slide numbers if `slideNumbers` are enabled
 				if( doingSlideNumbers ) {
-					let numberElement = document.createElement( 'div' );
+					const slideNumber = index + 1;
+					const numberElement = document.createElement( 'div' );
 					numberElement.classList.add( 'slide-number' );
 					numberElement.classList.add( 'slide-number-pdf' );
-					numberElement.innerHTML = slide.getAttribute( 'data-slide-number' );
+					numberElement.innerHTML = slideNumber;
 					page.appendChild( numberElement );
 				}

@@ -131,10 +162,9 @@ export default class Print {
 					// Each fragment 'group' is an array containing one or more
 					// fragments. Multiple fragments that appear at the same time
 					// are part of the same group.
-					let fragmentGroups = this.Reveal.fragments.sort( page.querySelectorAll( '.fragment' ), true );
+					const fragmentGroups = this.Reveal.fragments.sort( page.querySelectorAll( '.fragment' ), true );

 					let previousFragmentStep;
-					let previousPage;

 					fragmentGroups.forEach( function( fragments ) {

@@ -151,11 +181,10 @@ export default class Print {
 						}, this );

 						// Create a separate page for the current fragment state
-						let clonedPage = page.cloneNode( true );
-						page.parentNode.insertBefore( clonedPage, ( previousPage || page ).nextSibling );
+						const clonedPage = page.cloneNode( true );
+						pages.push( clonedPage );

 						previousFragmentStep = fragments;
-						previousPage = clonedPage;

 					}, this );

@@ -178,6 +207,10 @@ export default class Print {

 		}, this );

+		await new Promise( requestAnimationFrame );
+
+		pages.forEach( page => pageContainer.appendChild( page ) );
+
 		// Notify subscribers that the PDF layout is good to go
 		this.Reveal.dispatchEvent({ type: 'pdf-ready' });

@@ -192,4 +225,4 @@ export default class Print {

 	}

-}
+}
--- a/scripts/reveal.js/js/controllers/progress.js
+++ b/scripts/reveal.js/js/controllers/progress.js
@@ -88,16 +88,23 @@ export default class Progress {

 		event.preventDefault();

-		let slidesTotal = this.Reveal.getHorizontalSlides().length;
+		let slides = this.Reveal.getSlides();
+		let slidesTotal = slides.length;
 		let slideIndex = Math.floor( ( event.clientX / this.getMaxWidth() ) * slidesTotal );

 		if( this.Reveal.getConfig().rtl ) {
 			slideIndex = slidesTotal - slideIndex;
 		}

-		this.Reveal.slide( slideIndex );
+		let targetIndices = this.Reveal.getIndices(slides[slideIndex]);
+		this.Reveal.slide( targetIndices.h, targetIndices.v );

 	}

+	destroy() {
+
+		this.element.remove();
+
+	}

 }
--- a/scripts/reveal.js/js/controllers/slidecontent.js
+++ b/scripts/reveal.js/js/controllers/slidecontent.js
@@ -1,5 +1,4 @@
-import { HORIZONTAL_SLIDES_SELECTOR, VERTICAL_SLIDES_SELECTOR } from '../utils/constants.js'
-import { extend, queryAll, closest } from '../utils/util.js'
+import { extend, queryAll, closest, getMimeTypeFromFile } from '../utils/util.js'
 import { isMobile } from '../utils/device.js'

 import fitty from 'fitty';
@@ -102,7 +101,16 @@ export default class SlideContent {

 				// Images
 				if( backgroundImage ) {
-					backgroundContent.style.backgroundImage = 'url('+ encodeURI( backgroundImage ) +')';
+					// base64
+					if(  /^data:/.test( backgroundImage.trim() ) ) {
+						backgroundContent.style.backgroundImage = `url(${backgroundImage.trim()})`;
+					}
+					// URL(s)
+					else {
+						backgroundContent.style.backgroundImage = backgroundImage.split( ',' ).map( background => {
+							return `url(${encodeURI(background.trim())})`;
+						}).join( ',' );
+					}
 				}
 				// Videos
 				else if ( backgroundVideo && !this.Reveal.isSpeakerNotes() ) {
@@ -128,7 +136,13 @@ export default class SlideContent {

 					// Support comma separated lists of video sources
 					backgroundVideo.split( ',' ).forEach( source => {
-						video.innerHTML += '<source src="'+ source +'">';
+						let type = getMimeTypeFromFile( source );
+						if( type ) {
+							video.innerHTML += `<source src="${source}" type="${type}">`;
+						}
+						else {
+							video.innerHTML += `<source src="${source}">`;
+						}
 					} );

 					backgroundContent.appendChild( video );
@@ -167,11 +181,20 @@ export default class SlideContent {

 		}

+		this.layout( slide );
+
+	}
+
+	/**
+	 * Applies JS-dependent layout helpers for the given slide,
+	 * if there are any.
+	 */
+	layout( slide ) {
+
 		// Autosize text with the r-fit-text class based on the
 		// size of its container. This needs to happen after the
 		// slide is visible in order to measure the text.
-		Array.from( slide.querySelectorAll( '.r-fit-text:not([data-fitted])' ) ).forEach( element => {
-			element.dataset.fitted = '';
+		Array.from( slide.querySelectorAll( '.r-fit-text' ) ).forEach( element => {
 			fitty( element, {
 				minSize: 24,
 				maxSize: this.Reveal.getConfig().height * 0.8,
@@ -453,4 +476,4 @@ export default class SlideContent {

 	}

-}
+}
--- a/scripts/reveal.js/js/controllers/slidenumber.js
+++ b/scripts/reveal.js/js/controllers/slidenumber.js
@@ -123,4 +123,10 @@ export default class SlideNumber {

 	}

+	destroy() {
+
+		this.element.remove();
+
+	}
+
 }
--- a/scripts/reveal.js/js/controllers/touch.js
+++ b/scripts/reveal.js/js/controllers/touch.js
@@ -1,4 +1,5 @@
 import { isAndroid } from '../utils/device.js'
+import { matches } from '../utils/util.js'

 const SWIPE_THRESHOLD = 40;

@@ -82,6 +83,9 @@ export default class Touch {
 	 */
 	isSwipePrevented( target ) {

+		// Prevent accidental swipes when scrubbing timelines
+		if( matches( target, 'video, audio' ) ) return true;
+
 		while( target && typeof target.hasAttribute === 'function' ) {
 			if( target.hasAttribute( 'data-prevent-swipe' ) ) return true;
 			target = target.parentNode;
--- a/scripts/reveal.js/js/reveal.js
+++ b/scripts/reveal.js/js/reveal.js
@@ -26,14 +26,14 @@ import {
 } from './utils/constants.js'

 // The reveal.js version
-export const VERSION = '4.1.0';
+export const VERSION = '4.3.1';

 /**
 * reveal.js
 * https://revealjs.com
 * MIT licensed
 *
- * Copyright (C) 2020 Hakim El Hattab, https://hakim.se
+ * Copyright (C) 2011-2022 Hakim El Hattab, https://hakim.se
 */
 export default function( revealElement, options ) {

@@ -121,10 +121,14 @@ export default function( revealElement, options ) {
 	 */
 	function initialize( initOptions ) {

+		if( !revealElement ) throw 'Unable to find presentation root (<div class="reveal">).';
+
 		// Cache references to key DOM elements
 		dom.wrapper = revealElement;
 		dom.slides = revealElement.querySelector( '.slides' );

+		if( !dom.slides ) throw 'Unable to find slides container (<div class="slides">).';
+
 		// Compose our config object in order of increasing precedence:
 		// 1. Default reveal.js options
 		// 2. Options provided via Reveal.configure() prior to
@@ -186,6 +190,9 @@ export default function( revealElement, options ) {
 		// Prevent the slides from being scrolled out of view
 		setupScrollPrevention();

+		// Adds bindings for fullscreen mode
+		setupFullscreen();
+
 		// Resets all vertical slides so that only the first is visible
 		resetVerticalSlides();

@@ -372,6 +379,19 @@ export default function( revealElement, options ) {

 	}

+	/**
+	 * After entering fullscreen we need to force a layout to
+	 * get our presentations to scale correctly. This behavior
+	 * is inconsistent across browsers but a force layout seems
+	 * to normalize it.
+	 */
+	function setupFullscreen() {
+
+		document.addEventListener( 'fullscreenchange', onFullscreenChange );
+		document.addEventListener( 'webkitfullscreenchange', onFullscreenChange );
+
+	}
+
 	/**
 	 * Registers a listener to postMessage events, this makes it
 	 * possible to call all reveal.js API methods from another
@@ -385,32 +405,7 @@ export default function( revealElement, options ) {
 	function setupPostMessage() {

 		if( config.postMessage ) {
-			window.addEventListener( 'message', event => {
-				let data = event.data;
-
-				// Make sure we're dealing with JSON
-				if( typeof data === 'string' && data.charAt( 0 ) === '{' && data.charAt( data.length - 1 ) === '}' ) {
-					data = JSON.parse( data );
-
-					// Check if the requested method can be found
-					if( data.method && typeof Reveal[data.method] === 'function' ) {
-
-						if( POST_MESSAGE_METHOD_BLACKLIST.test( data.method ) === false ) {
-
-							const result = Reveal[data.method].apply( Reveal, data.args );
-
-							// Dispatch a postMessage event with the returned value from
-							// our method invocation for getter functions
-							dispatchPostMessage( 'callback', { method: data.method, result: result } );
-
-						}
-						else {
-							console.warn( 'reveal.js: "'+ data.method +'" is is blacklisted from the postMessage API' );
-						}
-
-					}
-				}
-			}, false );
+			window.addEventListener( 'message', onPostMessage, false );
 		}

 	}
@@ -525,6 +520,7 @@ export default function( revealElement, options ) {
 		controls.bind();
 		focus.bind();

+		dom.slides.addEventListener( 'click', onSlidesClicked, false );
 		dom.slides.addEventListener( 'transitionend', onTransitionEnd, false );
 		dom.pauseOverlay.addEventListener( 'click', resume, false );

@@ -550,11 +546,71 @@ export default function( revealElement, options ) {

 		window.removeEventListener( 'resize', onWindowResize, false );

+		dom.slides.removeEventListener( 'click', onSlidesClicked, false );
 		dom.slides.removeEventListener( 'transitionend', onTransitionEnd, false );
 		dom.pauseOverlay.removeEventListener( 'click', resume, false );

 	}

+	/**
+	 * Uninitializes reveal.js by undoing changes made to the
+	 * DOM and removing all event listeners.
+	 */
+	function destroy() {
+
+		removeEventListeners();
+		cancelAutoSlide();
+		disablePreviewLinks();
+
+		// Destroy controllers
+		notes.destroy();
+		focus.destroy();
+		plugins.destroy();
+		pointer.destroy();
+		controls.destroy();
+		progress.destroy();
+		backgrounds.destroy();
+		slideNumber.destroy();
+
+		// Remove event listeners
+		document.removeEventListener( 'fullscreenchange', onFullscreenChange );
+		document.removeEventListener( 'webkitfullscreenchange', onFullscreenChange );
+		document.removeEventListener( 'visibilitychange', onPageVisibilityChange, false );
+		window.removeEventListener( 'message', onPostMessage, false );
+		window.removeEventListener( 'load', layout, false );
+
+		// Undo DOM changes
+		if( dom.pauseOverlay ) dom.pauseOverlay.remove();
+		if( dom.statusElement ) dom.statusElement.remove();
+
+		document.documentElement.classList.remove( 'reveal-full-page' );
+
+		dom.wrapper.classList.remove( 'ready', 'center', 'has-horizontal-slides', 'has-vertical-slides' );
+		dom.wrapper.removeAttribute( 'data-transition-speed' );
+		dom.wrapper.removeAttribute( 'data-background-transition' );
+
+		dom.viewport.classList.remove( 'reveal-viewport' );
+		dom.viewport.style.removeProperty( '--slide-width' );
+		dom.viewport.style.removeProperty( '--slide-height' );
+
+		dom.slides.style.removeProperty( 'width' );
+		dom.slides.style.removeProperty( 'height' );
+		dom.slides.style.removeProperty( 'zoom' );
+		dom.slides.style.removeProperty( 'left' );
+		dom.slides.style.removeProperty( 'top' );
+		dom.slides.style.removeProperty( 'bottom' );
+		dom.slides.style.removeProperty( 'right' );
+		dom.slides.style.removeProperty( 'transform' );
+
+		Array.from( dom.wrapper.querySelectorAll( SLIDES_SELECTOR ) ).forEach( slide => {
+			slide.style.removeProperty( 'display' );
+			slide.style.removeProperty( 'top' );
+			slide.removeAttribute( 'hidden' );
+			slide.removeAttribute( 'aria-hidden' );
+		} );
+
+	}
+
 	/**
 	 * Adds a listener to one of our custom reveal.js events,
 	 * like slidechanged.
@@ -614,6 +670,8 @@ export default function( revealElement, options ) {
 			dispatchPostMessage( type );
 		}

+		return event;
+
 	}

 	/**
@@ -1188,9 +1246,22 @@ export default function( revealElement, options ) {
 	 * @param {number} [v=indexv] Vertical index of the target slide
 	 * @param {number} [f] Index of a fragment within the
 	 * target slide to activate
-	 * @param {number} [o] Origin for use in multimaster environments
+	 * @param {number} [origin] Origin for use in multimaster environments
 	 */
-	function slide( h, v, f, o ) {
+	function slide( h, v, f, origin ) {
+
+		// Dispatch an event before hte slide
+		const slidechange = dispatchEvent({
+			type: 'beforeslidechange',
+			data: {
+				indexh: h === undefined ? indexh : h,
+				indexv: v === undefined ? indexv : v,
+				origin
+			}
+		});
+
+		// Abort if this slide change was prevented by an event listener
+		if( slidechange.defaultPrevented ) return;

 		// Remember where we were at before
 		previousSlide = currentSlide;
@@ -1251,7 +1322,10 @@ export default function( revealElement, options ) {
 			// Note 20-03-2020:
 			// This needs to happen before we update slide visibility,
 			// otherwise transitions will still run in Safari.
-			if( previousSlide.hasAttribute( 'data-auto-animate' ) && currentSlide.hasAttribute( 'data-auto-animate' ) ) {
+			if( previousSlide.hasAttribute( 'data-auto-animate' ) && currentSlide.hasAttribute( 'data-auto-animate' )
+					&& previousSlide.getAttribute( 'data-auto-animate-id' ) === currentSlide.getAttribute( 'data-auto-animate-id' )
+					&& !( ( indexh > indexhBefore || indexv > indexvBefore ) ? currentSlide : previousSlide ).hasAttribute( 'data-auto-animate-restart' ) ) {
+
 				autoAnimateTransition = true;
 				dom.slides.classList.add( 'disable-slide-transitions' );
 			}
@@ -1323,7 +1397,7 @@ export default function( revealElement, options ) {
 					indexv,
 					previousSlide,
 					currentSlide,
-					origin: o
+					origin
 				}
 			});
 		}
@@ -1335,7 +1409,11 @@ export default function( revealElement, options ) {
 		}

 		// Announce the current slide contents to screen readers
-		announceStatus( getStatusText( currentSlide ) );
+		// Use animation frame to prevent getComputedStyle in getStatusText
+		// from triggering layout mid-frame
+		requestAnimationFrame( () => {
+			announceStatus( getStatusText( currentSlide ) );
+		});

 		progress.update();
 		controls.update();
@@ -2186,55 +2264,55 @@ export default function( revealElement, options ) {

 	}

-	function navigateLeft() {
+	function navigateLeft({skipFragments=false}={}) {

 		navigationHistory.hasNavigatedHorizontally = true;

 		// Reverse for RTL
 		if( config.rtl ) {
-			if( ( overview.isActive() || fragments.next() === false ) && availableRoutes().left ) {
+			if( ( overview.isActive() || skipFragments || fragments.next() === false ) && availableRoutes().left ) {
 				slide( indexh + 1, config.navigationMode === 'grid' ? indexv : undefined );
 			}
 		}
 		// Normal navigation
-		else if( ( overview.isActive() || fragments.prev() === false ) && availableRoutes().left ) {
+		else if( ( overview.isActive() || skipFragments || fragments.prev() === false ) && availableRoutes().left ) {
 			slide( indexh - 1, config.navigationMode === 'grid' ? indexv : undefined );
 		}

 	}

-	function navigateRight() {
+	function navigateRight({skipFragments=false}={}) {

 		navigationHistory.hasNavigatedHorizontally = true;

 		// Reverse for RTL
 		if( config.rtl ) {
-			if( ( overview.isActive() || fragments.prev() === false ) && availableRoutes().right ) {
+			if( ( overview.isActive() || skipFragments || fragments.prev() === false ) && availableRoutes().right ) {
 				slide( indexh - 1, config.navigationMode === 'grid' ? indexv : undefined );
 			}
 		}
 		// Normal navigation
-		else if( ( overview.isActive() || fragments.next() === false ) && availableRoutes().right ) {
+		else if( ( overview.isActive() || skipFragments || fragments.next() === false ) && availableRoutes().right ) {
 			slide( indexh + 1, config.navigationMode === 'grid' ? indexv : undefined );
 		}

 	}

-	function navigateUp() {
+	function navigateUp({skipFragments=false}={}) {

 		// Prioritize hiding fragments
-		if( ( overview.isActive() || fragments.prev() === false ) && availableRoutes().up ) {
+		if( ( overview.isActive() || skipFragments || fragments.prev() === false ) && availableRoutes().up ) {
 			slide( indexh, indexv - 1 );
 		}

 	}

-	function navigateDown() {
+	function navigateDown({skipFragments=false}={}) {

 		navigationHistory.hasNavigatedVertically = true;

 		// Prioritize revealing fragments
-		if( ( overview.isActive() || fragments.next() === false ) && availableRoutes().down ) {
+		if( ( overview.isActive() || skipFragments || fragments.next() === false ) && availableRoutes().down ) {
 			slide( indexh, indexv + 1 );
 		}

@@ -2246,12 +2324,12 @@ export default function( revealElement, options ) {
 	 * 2) Previous vertical slide
 	 * 3) Previous horizontal slide
 	 */
-	function navigatePrev() {
+	function navigatePrev({skipFragments=false}={}) {

 		// Prioritize revealing fragments
-		if( fragments.prev() === false ) {
+		if( skipFragments || fragments.prev() === false ) {
 			if( availableRoutes().up ) {
-				navigateUp();
+				navigateUp({skipFragments});
 			}
 			else {
 				// Fetch the previous horizontal slide, if there is one
@@ -2264,11 +2342,16 @@ export default function( revealElement, options ) {
 					previousSlide = Util.queryAll( dom.wrapper, HORIZONTAL_SLIDES_SELECTOR + '.past' ).pop();
 				}

-				if( previousSlide ) {
+				// When going backwards and arriving on a stack we start
+				// at the bottom of the stack
+				if( previousSlide && previousSlide.classList.contains( 'stack' ) ) {
 					let v = ( previousSlide.querySelectorAll( 'section' ).length - 1 ) || undefined;
 					let h = indexh - 1;
 					slide( h, v );
 				}
+				else {
+					navigateLeft({skipFragments});
+				}
 			}
 		}

@@ -2277,31 +2360,31 @@ export default function( revealElement, options ) {
 	/**
 	 * The reverse of #navigatePrev().
 	 */
-	function navigateNext() {
+	function navigateNext({skipFragments=false}={}) {

 		navigationHistory.hasNavigatedHorizontally = true;
 		navigationHistory.hasNavigatedVertically = true;

 		// Prioritize revealing fragments
-		if( fragments.next() === false ) {
+		if( skipFragments || fragments.next() === false ) {

 			let routes = availableRoutes();

 			// When looping is enabled `routes.down` is always available
 			// so we need a separate check for when we've reached the
 			// end of a stack and should move horizontally
-			if( routes.down && routes.right && config.loop && isLastVerticalSlide( currentSlide ) ) {
+			if( routes.down && routes.right && config.loop && isLastVerticalSlide() ) {
 				routes.down = false;
 			}

 			if( routes.down ) {
-				navigateDown();
+				navigateDown({skipFragments});
 			}
 			else if( config.rtl ) {
-				navigateLeft();
+				navigateLeft({skipFragments});
 			}
 			else {
-				navigateRight();
+				navigateRight({skipFragments});
 			}
 		}

@@ -2326,6 +2409,38 @@ export default function( revealElement, options ) {

 	}

+	/**
+	* Listener for post message events posted to this window.
+	*/
+	function onPostMessage( event ) {
+
+		let data = event.data;
+
+		// Make sure we're dealing with JSON
+		if( typeof data === 'string' && data.charAt( 0 ) === '{' && data.charAt( data.length - 1 ) === '}' ) {
+			data = JSON.parse( data );
+
+			// Check if the requested method can be found
+			if( data.method && typeof Reveal[data.method] === 'function' ) {
+
+				if( POST_MESSAGE_METHOD_BLACKLIST.test( data.method ) === false ) {
+
+					const result = Reveal[data.method].apply( Reveal, data.args );
+
+					// Dispatch a postMessage event with the returned value from
+					// our method invocation for getter functions
+					dispatchPostMessage( 'callback', { method: data.method, result: result } );
+
+				}
+				else {
+					console.warn( 'reveal.js: "'+ data.method +'" is is blacklisted from the postMessage API' );
+				}
+
+			}
+		}
+
+	}
+
 	/**
 	 * Event listener for transition end on the current slide.
 	 *
@@ -2343,6 +2458,33 @@ export default function( revealElement, options ) {

 	}

+	/**
+	 * A global listener for all click events inside of the
+	 * .slides container.
+	 *
+	 * @param {object} [event]
+	 */
+	function onSlidesClicked( event ) {
+
+		const anchor = Util.closest( event.target, 'a[href^="#"]' );
+
+		// If a hash link is clicked, we find the target slide
+		// and navigate to it. We previously relied on 'hashchange'
+		// for links like these but that prevented media with
+		// audio tracks from playing in mobile browsers since it
+		// wasn't considered a direct interaction with the document.
+		if( anchor ) {
+			const hash = anchor.getAttribute( 'href' );
+			const indices = location.getIndicesFromHash( hash );
+
+			if( indices ) {
+				Reveal.slide( indices.h, indices.v, indices.f );
+				event.preventDefault();
+			}
+		}
+
+	}
+
 	/**
 	 * Handler for the window level 'resize' event.
 	 *
@@ -2373,6 +2515,26 @@ export default function( revealElement, options ) {

 	}

+	/**
+	 * Handler for the document level 'fullscreenchange' event.
+	 *
+	 * @param {object} [event]
+	 */
+	function onFullscreenChange( event ) {
+
+		let element = document.fullscreenElement || document.webkitFullscreenElement;
+		if( element === dom.wrapper ) {
+			event.stopImmediatePropagation();
+
+			// Timeout to avoid layout shift in Safari
+			setTimeout( () => {
+				Reveal.layout();
+				Reveal.focus.focus(); // focus.focus :'(
+			}, 1 );
+		}
+
+	}
+
 	/**
 	 * Handles clicks on links that are set to preview in the
 	 * iframe overlay.
@@ -2425,6 +2587,7 @@ export default function( revealElement, options ) {

 		initialize,
 		configure,
+		destroy,

 		sync,
 		syncSlide,
@@ -2500,6 +2663,10 @@ export default function( revealElement, options ) {
 		loadSlide: slideContent.load.bind( slideContent ),
 		unloadSlide: slideContent.unload.bind( slideContent ),

+		// Preview management
+		showPreview,
+		hidePreview: closeOverlay,
+
 		// Adds or removes all internal event listeners
 		addEventListeners,
 		removeEventListeners,
@@ -2577,6 +2744,9 @@ export default function( revealElement, options ) {
 		// Helper method, retrieves query string as a key:value map
 		getQueryHash: Util.getQueryHash,

+		// Returns the path to the current slide as represented in the URL
+		getSlidePath: location.getHash.bind( location ),
+
 		// Returns reveal.js DOM elements
 		getRevealElement: () => revealElement,
 		getSlidesElement: () => dom.slides,
--- a/scripts/reveal.js/js/utils/color.js
+++ b/scripts/reveal.js/js/utils/color.js
@@ -29,9 +29,9 @@ export const colorToRgb = ( color ) => {
 	if( hex6 && hex6[1] ) {
 		hex6 = hex6[1];
 		return {
-			r: parseInt( hex6.substr( 0, 2 ), 16 ),
-			g: parseInt( hex6.substr( 2, 2 ), 16 ),
-			b: parseInt( hex6.substr( 4, 2 ), 16 )
+			r: parseInt( hex6.slice( 0, 2 ), 16 ),
+			g: parseInt( hex6.slice( 2, 4 ), 16 ),
+			b: parseInt( hex6.slice( 4, 6 ), 16 )
 		};
 	}

--- a/scripts/reveal.js/js/utils/util.js
+++ b/scripts/reveal.js/js/utils/util.js
@@ -279,4 +279,19 @@ export const getRemainingHeight = ( element, height = 0 ) => {

 	return height;

+}
+
+const fileExtensionToMimeMap = {
+	'mp4': 'video/mp4',
+	'm4a': 'video/mp4',
+	'ogv': 'video/ogg',
+	'mpeg': 'video/mpeg',
+	'webm': 'video/webm'
+}
+
+/**
+ * Guess the MIME type for common file formats.
+ */
+export const getMimeTypeFromFile = ( filename='' ) => {
+	return fileExtensionToMimeMap[filename.split('.').pop()]
 }