uweb/zh/searchurl/bml/content/read.js

/**
 * Make a page more readable by disabling all page styling and applying a
 * bare minimum of our own. Go to the first thing that looks like the start
 * of the actual content so no time is wasted scrolling past initial
 * navigation etc.
 *
 * @title Readable++
 */
(function read() {
	/* Create a new IFRAME to get a "clean" Window object, so we can use its
	 * console. Sometimes sites (e.g. Twitter) override console.log and even
	 * the entire console object. "delete console.log" or "delete console"
	 * does not always work, and messing with the prototype seemed more
	 * brittle than this. */
	var console = (function () {
		var iframe = document.getElementById('xxxJanConsole');
		if (!iframe) {
			iframe = document.createElementNS('http://www.w3.org/1999/xhtml', 'iframe');
			iframe.id = 'xxxJanConsole';
			iframe.style.display = 'none';

			(document.body || document.documentElement).appendChild(iframe);
		}

		return iframe && iframe.contentWindow && iframe.contentWindow.console || {
			log: function () {}
		};
	})();

	/* The style sheet for more readable content. */
	var css = (function () { /*@charset "utf-8";
		@namespace svg "http://www.w3.org/2000/svg";

		-jancss-comment { content:
			"General styles -------------------------------------------";
		}

		* {
			line-height: 1.5;
		}

		html {
			background: rgb(245, 245, 225);
			color: rgb(0, 0, 30);
		}

		body {
			max-width: 48em;
			margin: 0 auto;
			padding: 1em;
			font-family: "Calibri", sans-serif;
			font-size: 1.05rem;
		}

		p {
			line-height: 1.7;
		}

		:link {
			color: #00e;
		}

		:visited {
			color: #528;
		}

		:link:focus,
		:visited:focus,
		:link:hover,
		:visited:hover {
			color: #e30;
		}

		:link:active,
		:visited:active {
			color: #e00;
		}

		center,
		[align] {
			text-align: left;
		}

		b:not(.jancss-probably-structure),
		u,
		blink {
			font-weight: inherit;
			font-style: inherit;
			text-decoration: inherit
		}

		b.jancss-probably-structure {
			font-size: larger;
		}

		.jancss-probably-layout {
			font: inherit;
		}

		-jancss-comment { content:
			"Headers --------------------------------------------------";
		}

		h1:not(.jancss-probably-layout),
		h2:not(.jancss-probably-layout),
		h3:not(.jancss-probably-layout) {
			font-family: "Cambria", serif;
		}

		h1, h1.jancss-probably-layout {
			border-bottom: 1px solid #888;
			font-size: 200%;
			font-weight: 100;
		}

		h2, h2.jancss-probably-layout * {
			border-bottom: 1px solid #bbb;
			font-size: 150%;
			font-weight: 100;
		}

		h3, h3.jancss-probably-layout {
			border-bottom: 1px dotted #bbb;
			font-size: 117%;
			font-weight: 100;
		}

		h1.jancss-probably-layout *,
		h2.jancss-probably-layout *,
		h3.jancss-probably-layout * {
			font-size: 1rem;
		}

		-jancss-comment { content:
			"Links in headers (probably permalinks) -------------------";
		}

		h1 a[href]:not(:hover),
		h2 a[href]:not(:hover),
		h3 a[href]:not(:hover) {
			text-decoration: none;
		}

		h1 a[href]::after,
		h2 a[href]::after,
		h3 a[href]::after {
			font-size: 75%;
			content: " #";
		}

		-jancss-comment { content:
			"Pre-formatted text and source code -----------------------";
		}

		pre {
			padding: 1ex;
			border: 1px dotted;
		}

		code,
		pre,
		.syntaxhighlighter,
		.dp-highlighter {
			font-family: "Consolas", monospace;
			font-size: small;
			background: #ffe;
		}

		.dp-highlighter + pre[name="code"] {
			display: none;
		}

		-jancss-comment { content:
			"Forms ----------------------------------------------------";
		}

		textarea {
			width: 100%;
			height: 32ex;
		}

		-jancss-comment { content:
			"Tables ---------------------------------------------------";
		}

		table.jancss-probably-for-data th,
		table.jancss-probably-for-data td {
			vertical-align: top;
			text-align: left;
			padding: 0.5ex;
		}

		table.jancss-probably-for-data caption {
			font-weight: bold;
			border-bottom: 1px dotted;
		}

		table.jancss-probably-for-layout td {
			display: inline-block;
		}

		table.jancss-probably-for-data tr:nth-child(odd) td:not(.jancss-active-col) {
			background: #ffe;
		}

		table.jancss-probably-for-data tr:hover td:not(.code),
		table.jancss-probably-for-data .jancss-active-col {
			background: #ffc;
		}

		table.jancss-probably-for-data th,
		table.jancss-probably-for-data tr td:not(.code):hover {
			background: #ff9;
		}

		table.jancss-probably-for-data th code,
		table.jancss-probably-for-data td code {
			background: inherit;
		}

		-jancss-comment { content:
			"Make images use the full page width ----------------------";
		}

		img,
		input[type="image"],
		object,
		embed,
		video,
		audio,
		iframe,
		canvas,
		:not(svg|*) > svg|* {
			max-width: 100%;
		}

		figure {
			margin: 0;
		}

		iframe {
			width: 100%;
		}

		iframe[class*="twitter"] {
			min-height: 15em;
		}

		-jancss-comment { content:
			"Dim images and media until :hover ------------------------";
		}

		body:not(:hover) img,
		body:not(:hover) input[type="image"],
		body:not(:hover) object,
		body:not(:hover) embed,
		body:not(:hover) video,
		body:not(:hover) audio,
		body:not(:hover) iframe,
		body:not(:hover) canvas,
		body:not(:hover) :not(svg|*) > svg|* {
			opacity: 0.25;
		}

		-jancss-comment { content:
			"Limit icon dimensions --------------------------------";
		}

		a[href*="facebook.com"] svg,
		a[href*="instagram.com"] svg,
		a[href*="twitter.com"] svg,
		a[href*=".pinterest."] svg,
		svg[id*="icon"],
		svg[class*="icon"],
		svg[class*="inline"],
		svg[data-icon],
		svg[role="img"],
		[class*="icon"] svg,
		[class*="Icon"] svg,
		img[class*="icon"][src*=".svg"],
		img[class*="Icon"][src*=".svg"],
		span > svg,
		button svg,
		[class*="button"] svg,
		[role*="button"] svg,
		[class*="controls"] svg,
		.svg-icon,
		.inline-icon,
		.wp-smiley,
		.smiley,
		.emoticon,
		:not(html).emoji {
			max-width: 1.4em;
			max-height: 1.4em;
		}

		-jancss-comment { content:
			"Make everything scrollable -------------------------------";
		}

		[style*="position: fixed"],
		[style*="position:fixed"] {
			position: static !important;
		}

		-jancss-comment { content:
			"Make side notes and pull quotes less conspicuous ---------";
		}

		aside:not(:hover),
		[data-expander-id],
		[id^="footnote_plugin_tooltip_text_"]:not(:hover),
		blockquote[class*="quote"]:not(:hover),
		q[class*="pull"]:not(:hover),
		blockquote[class*="pull"]:not(:hover),
		.quote-box:not(:hover),
		.su-pullquote:not(:hover),
		.pullquote:not(:hover),
		.pullQuote:not(:hover),
		.pull-quote:not(:hover) {
			opacity: 0.25;
		}

		-jancss-comment { content:
			"Decrease common forum and metadata font size -------------";
		}

		.postprofile,
		.signature {
			font-size: smaller;
			border-top: 1px dotted;
			opacity: 0.5;
		}

		-jancss-comment { content:
			"Hide common social media elements ------------------------";
		}

		iframe[src*=".facebook.com/"],
		iframe[src*=".twitter.com/widgets/"],
		iframe[src*="//plusone.google.com/_/+1/"],
		iframe[src*="//www.reddit.com/static/button/"],
		iframe[src*="//s7.addthis.com/"],
		iframe[src*="//www.stumbleupon.com/badge/embed/"],
		iframe[src*="//widgets.bufferapp.com/"] {
			width: 12em;
			height: 4ex;
			border: 1px dotted;
		}

		.twtr-widget.twtr-scroll {
			max-height: 30ex;
			overflow: auto;
		}

		.article__share {
			display: none;
		}

		#social_btns {
			display: none;
		}

		.taboola {
			display: none;
		}

		.social-media > .share {
			display: none;
		}

		:-moz-any(
			div,
			ul,
			li
		):-moz-any(
			:-moz-any(
				[id*="social"],
				[id*="Social"]
			):-moz-any(
				[id*="media"],
				[id*="Media"]
			):-moz-any(
				[id*="share"],
				[id*="Share"],
				[id*="sharing"],
				[id*="Sharing"]
			),
			:-moz-any(
				[id*="social"],
				[id*="Social"]
				[id*="share"],
				[id*="Share"],
				[id*="sharing"],
				[id*="Sharing"]
			):-moz-any(
				[id*="toolbar"],
				[id*="Toolbar"],
				[id*="buttons"],
				[id*="Buttons"],
			),
			:-moz-any(
				[class*="social"],
				[class*="Social"]
			):-moz-any(
				[class*="media"],
				[class*="Media"]
			):-moz-any(
				[class*="share"],
				[class*="Share"],
				[class*="sharing"],
				[class*="Sharing"]
			),
			:-moz-any(
				[class*="social"],
				[class*="Social"]
				[class*="share"],
				[class*="Share"],
				[class*="sharing"],
				[class*="Sharing"]
			):-moz-any(
				[class*="toolbar"],
				[class*="Toolbar"],
				[class*="buttons"],
				[class*="Buttons"],
			)
		) {
			display: none;
		}

		:matches(
			div,
			ul,
			li
		):matches(
			:matches(
				[id*="social"],
				[id*="Social"]
			):matches(
				[id*="media"],
				[id*="Media"]
			):matches(
				[id*="share"],
				[id*="Share"],
				[id*="sharing"],
				[id*="Sharing"]
			),
			:matches(
				[id*="social"],
				[id*="Social"]
				[id*="share"],
				[id*="Share"],
				[id*="sharing"],
				[id*="Sharing"]
			):matches(
				[id*="toolbar"],
				[id*="Toolbar"],
				[id*="buttons"],
				[id*="Buttons"],
			),
			:matches(
				[class*="social"],
				[class*="Social"]
			):matches(
				[class*="media"],
				[class*="Media"]
			):matches(
				[class*="share"],
				[class*="Share"],
				[class*="sharing"],
				[class*="Sharing"]
			),
			:matches(
				[class*="social"],
				[class*="Social"]
				[class*="share"],
				[class*="Share"],
				[class*="sharing"],
				[class*="Sharing"]
			):matches(
				[class*="toolbar"],
				[class*="Toolbar"],
				[class*="buttons"],
				[class*="Buttons"],
			)
		) {
			display: none;
		}

		-jancss-comment { content:
			"Hide ad elements that slipped through my ad blocker ------";
		}

		iframe[id^="google_ads_"] {
			display: none;
		}

		-jancss-comment { content:
			"Hide empty list items ------------------------------------";
		}

		li:empty, li.jancss-emptyish {
			display: none;
		}

		-jancss-comment { content:
			"Make common navigation elements more compact -------------";
		}

		:-moz-any(
			nav,
			body [class*="avigat"],
			body [id*="avigat"],
			body [class*="-nav-"],
			body [class*="nav-"],
			body [class$="-nav"],
			body [id*="-nav-"],
			body [id*="nav-"],
			body [id$="-nav"],
			body [role="navigation"]
		) ul {
			display: inline;
			margin: 0;
			padding: 0;
		}

		:-webkit-any(
			nav,
			body [class*="avigat"],
			body [id*="avigat"],
			body [class*="-nav-"],
			body [class*="nav-"],
			body [class$="-nav"],
			body [id*="-nav-"],
			body [id*="nav-"],
			body [id$="-nav"],
			body [role="navigation"]
		) ul {
			display: inline;
			margin: 0;
			padding: 0;
		}

		:any(
			nav,
			body [class*="avigat"],
			body [id*="avigat"],
			body [class*="-nav-"],
			body [class*="nav-"],
			body [class$="-nav"],
			body [id*="-nav-"],
			body [id*="nav-"],
			body [id$="-nav"],
			body [role="navigation"]
		) ul {
			display: inline;
			margin: 0;
			padding: 0;
		}

		:-moz-any(
			nav,
			body [class*="avigat"],
			body [id*="avigat"],
			body [class*="-nav-"],
			body [class*="nav-"],
			body [class$="-nav"],
			body [id*="-nav-"],
			body [id*="nav-"],
			body [id$="-nav"],
			body [role="navigation"]
		) li {
			display: inline;
			margin: 0;
			padding: 0 .5em;
			border-right: 1px dotted;
		}

		:-webkit-any(
			nav,
			body [class*="avigat"],
			body [id*="avigat"],
			body [class*="-nav-"],
			body [class*="nav-"],
			body [class$="-nav"],
			body [id*="-nav-"],
			body [id*="nav-"],
			body [id$="-nav"],
			body [role="navigation"]
		) li {
			display: inline;
			margin: 0;
			padding: 0 .5em;
			border-right: 1px dotted;
		}

		:any(
			nav,
			body [class*="avigat"],
			body [id*="avigat"],
			body [class*="-nav-"],
			body [class*="nav-"],
			body [class$="-nav"],
			body [id*="-nav-"],
			body [id*="nav-"],
			body [id$="-nav"],
			body [role="navigation"]
		) li {
			display: inline;
			margin: 0;
			padding: 0 .5em;
			border-right: 1px dotted;
		}

		-jancss-comment { content:
			"Hide old cufón text replacement --------------------------";
		}

		.cufon-canvas canvas {
			display: none;
		}

		-jancss-comment { content:
			"Make notes on decorrespondent.nl less conspicuous --------";
		}

		.contentitem-sidenote:not(:hover) > :not(.contentitem-sidenote-snippet),
		.contentitem-infocard-toggle-container + .contentitem-infocard-contents:not(:hover) {
			opacity: 0.25;
		}

		.contentitem-sidenote:hover > :not(.contentitem-sidenote-snippet),
		.contentitem-infocard-toggle-container + .contentitem-infocard-contents:hover {
			background: #ffc;
		}

		-jancss-comment { content:
			"Hide the source text on Google Translate-d pages ---------";
		}

		.google-src-text {
			display: none;
		}

		-jancss-comment { content:
			"Hide big ScrollMagic spacers, e.g. on Co.Design ----------";
		}

		.scrollmagic-pin-spacer {
			display: none;
		}

		-jancss-comment { content:
			"Always hide our IFRAME used to restore console.log -------";
		}

		#xxxJanConsole {
			display: none;
		}

	*/; }).toString()
		.replace(/^function\s*\(\s*\)\s*\{\s*\/\*/, '')
		.replace(/\*\/\s*\;?\s*\}\s*$/, '');

	/* The attributes to disable. */
	var attrs = [
		'style',
		'background', 'bgcolor', 'color', 'text', 'link', 'vlink', 'alink', 'hlink',
		'table@width', 'colgroup@width', 'col@width', 'tr@width', 'td@width', 'th@width', 'table@height', 'tr@height', 'td@height', 'th@height',
		'img@width', 'img@height',
		'border',
		'frameborder',
		'align',
		'face', 'font@size', 'basefont@size'
	];

	/* Elements to remove completely. */
	var elementsToRemoveSelectors = [
		'.bt-popin' /* Used on standaard.be. */
	];

	/* The selectors to try for the header elements, whose text content will be compared to the page title. The last match wins. */
	var headerSelectors = [
		'[class*="head"]:not(:empty)',
		'[class*="Head"]:not(:empty)',
		'[id*="head"]:not(:empty)',
		'[id*="Head"]:not(:empty)',
		'[role="heading"]',
		'[class*="title"]:not(:empty)',
		'[class*="Title"]:not(:empty)',
		'h1:not(:empty), h2:not(:empty), h3:not(:empty)',
		'h1:not(:empty)[itemprop~="name"], h2:not(:empty)[itemprop~="name"], h3:not(:empty)[itemprop~="name"]',
		'h1:not(:empty)[itemprop~="headline"], h2:not(:empty)[itemprop~="headline"], h3:not(:empty)[itemprop~="headline"]'
	];

	var ancestorsForHeadersToIgnoreSelectors = [
		'aside',
		'.related-posts',
		'.article-slider',
		'.article-drawer'
	];

	/* The selectors to try (in this order) for the first content element to scroll to when no suitable header was found. */
	var contentSelectors = [
		/* The most semantically rich elements should be used correctly so we
		 * can ass-u-me them to be the main content element, right?
		 */
		'main h1:not(:empty)',
		'main header',
		'main h2:not(:empty)',
		'main',
		'body [itemprop="blogPost"] h1:not(:empty)',
		'body [itemprop="blogPost"] header',
		'body [itemprop="blogPost"] h2:not(:empty)',
		'body [itemprop="blogPost"]',
		'body [role="main"] h1:not(:empty)',
		'body [role="main"] header',
		'body [role="main"] h2:not(:empty)',
		'body [role="main"]',
		'body [role="document"] h1:not(:empty)',
		'body [role="document"] header',
		'body [role="document"] h2:not(:empty)',
		'body [role="document"]',
		'body [role="article"] h1:not(:empty)',
		'body [role="article"] header',
		'body [role="article"] h2:not(:empty)',
		'body [role="article"]',
		'body #main h1:not(:empty)',
		'body #main header',
		'body #main h2:not(:empty)',
		'body #main',

		/* <article> is also "semantically rich", but there are several sites
		 * that have a list of related articles, each in its own <article>. A
		 * "real" article would not have any <article> siblings.
		 */
		':not(li) > article:only-of-type',

		/* Common IDs and classes for the main content element (e.g. weblog
		 * post IDs, newspaper articles, …)
		 */
		'body #article',
		'body :not(#spotlight) > .article',
		'body .articleContent',
		'body #article_top',
		'body #article_body',
		'body #article_main',
		'body .post-body:not(.field-item)',
		':not(input):not(textarea).post',
		':not(input):not(textarea).blogpost',
		':not(input):not(textarea).blogPost',
		'body [id^="post0"]',
		'body [id^="post1"]',
		'body [id^="post2"]',
		'body [id^="post3"]',
		'body [id^="post4"]',
		'body [id^="post5"]',
		'body [id^="post6"]',
		'body [id^="post7"]',
		'body [id^="post8"]',
		'body [id^="post9"]',
		'body [id^="post-0"]',
		'body [id^="post-1"]',
		'body [id^="post-2"]',
		'body [id^="post-3"]',
		'body [id^="post-4"]',
		'body [id^="post-5"]',
		'body [id^="post-6"]',
		'body [id^="post-7"]',
		'body [id^="post-8"]',
		'body [id^="post-9"]',
		'body #entry',
		'body .entry',
		'body #content',
		'body .content',
		'body [id^="content"]',
		'body [class^="content"]',
		'body #main',
		'body .main',

		/* Consider the first header (in DOM order) to be the most important
		 * one and ass-u-me it is the start of the main content.
		 */
		'h1:not(:empty)',
		'body #header',
		'header',
		'body .header',
		'h2:not(:empty)',

		/* When all else fails, just look for bigger text, which would
		 * probably be used instead of the appropriate header elements.
		 */
		'big'
	];

	/* Structure elements incorrectly used for layout purposes ("make it big and bold"). */
	var structureElementsForLayoutSelectors = [
		'//*[contains(" h1 h2 h3 h4 h5 h6 h7 ", concat(" ", local-name(), " ")) and string-length(normalize-space()) > 120]'
	];

	/* Layout elements incorrectly used for structure purposes ("bold means header"). */
	var layoutElementsForStructureSelectors = [
		/* Because there is no support for the Selectors Level 4 "subject of
		 * a selector" syntax yet (or any definite syntax, for that matter),
		 * I simply ass-u-me in the code below that the subject is a "B"
		 * element. Either the result of the selector, or the previous
		 * element sibling.
		 */
		'b:first-child + :empty',
		':empty + b + :empty',
		':empty + b:last-child',
		'div > b:only-child, p > b:only-child'
	];

	/* URI pattern for syntax highlighting style sheets. */
	var syntaxHighlightHrefRegex = /\b((syntax|pygments)(hi(ghlight(er)?|lite(r)?))?|sh(Core|Theme[^.]*)|geshi|codecolorer)[./]/i;

	/* Keep track of which elements have had their event handlers
	 * disabled/re-enabled.
	 */
	var elementsWithToggledEventHandlers = {};

	var eventHandlerAttributesToToggle = [
		'oncontextmenu',
		'onshow',

		'oninput',
		'onkeydown',
		'onkeyup',
		'onkeypress',

		'onmousedown',
		'onmouseup',
		'onmouseenter',
		'onmouseleave',
		'onmouseover',
		'onmouseout',
		'onmousemove',

		'onresize',

		'onscroll',
		'onwheel',

		'onselect',
		'onselectstart',
		'onselectionchange'
	];

	/* All main content elements (the one in the main document and those
	 * nested in any IFRAMEs etc.) */
	var contentElements = [];

	/* The main function. */
	(function execute(document) {
		function addClass(element, classNames) {
			/* HTMLElement.classList does not work on iOS 4's Safari, so this is a fallback. */
			classNames.split(/\s+/).forEach(function (className) {
				element.className = ((' ' + element.className + ' ').replace(' ' + className.trim() + ' ', '') + ' ' + className).trim();
			});
		}

		function removeClass(element, classNames) {
			classNames.split(/\s+/).forEach(function (className) {
				element.className = (' ' + element.className + ' ').replace(' ' + className.trim() + ' ', '').trim();
			});
		}

		function toArray(arrayLike) {
			return Array.prototype.slice.call(arrayLike);
		}

		var all = toArray(document.getElementsByTagName('*')),
		    ourStyleSheet = document.getElementById('jancss'),
		    allStyleSheets = toArray(document.styleSheets),
		    prettyPrintStyleSheet,
		    matches;

		/* Special hack for The Guardian (and possibly others), which re-enables the CSS because it detects a change in font size. */
		window.TextResizeDetector && TextResizeDetector.stopDetector && TextResizeDetector.stopDetector();

		/* Clear all scheduled callbacks. Naively ass-u-me that any call to
		 * setTimeout/setInterval returns the next ID from a monotonically
		 * increasing function that is used for both timeout and interval
		 * IDs. Therefore, to clear all timeouts and intervals, it suffices
		 * to get a new timeout ID and then clear everything up to that ID.
		 *
		 * Though the HTML5 specification says nothing about the return value
		 * of setTimeout/setInterval, this appears to work in Firefox 22,
		 * Chrome 27, Opera 12 and Safari 5.
		 */
		var maxTimeoutId = setTimeout(function () {
			for (var i = 1; i < maxTimeoutId; i++) {
				clearTimeout(i);
				clearInterval(i);
			}
		}, 4); /* 4 ms is the minimum timeout as per HTML5. */

		/* Now clear all the requested animation frame callbacks. Again, this
		 * naively assumes the ID will increment one by one. MDN explicitly
		 * advises against assumptions such as this one: https://developer.mozilla.org/en-US/docs/Web/API/window.requestAnimationFrame#Return_value
		 */
		var requestAnimationFrame = window.requestAnimationFrame
			|| window.mozRequestAnimationFrame
			|| window.webkitRequestAnimationFrame
			|| window.msRequestAnimationFrame
			|| function () { };

		var cancelAnimationFrame = window.cancelAnimationFrame
			|| window.mozCancelAnimationFrame
			|| window.webkitCancelAnimationFrame
			|| window.msCancelAnimationFrame
			|| function () { };

		var maxAnimationFrameRequestId = requestAnimationFrame(function () {
			for (i = 1; i < maxAnimationFrameRequestId * 2; i++) {
				cancelAnimationFrame(i);
			}

			/* Log requests to the original requestAnimationFrame. */
			window.requestAnimationFrame = function (callback) {
				var callbackSource = callback.toSource && callback.toSource();
				if (callbackSource && callbackSource.indexOf('Readable++ requestAnimationFrame interceptor') === -1) {
					console.log('Readable++: intercepted call to requestAnimationFrame at ' + new Date());
					console.log('Readable++: callback for requestAnimationFrame: ' + callbackSource);
				}
			};
		});

		/* While in Readable++ mode, disable some elements' event handlers.
		 * This prevents hijacking events like "scroll" and "resize", which
		 * can be abused to annoy me with visual effects and whatnot, and
		 * "contextmenu" and "selectstart", which are clearly defined as
		 * universal and inalienable human rights. Look it up at your local
		 * Wikipedia office.
		 */
		[window, document, document.documentElement, document.body].forEach(function (elem) {
			/* In non-HTML documents, elements like document.body can be
			 * null. */
			if (!elem) {
				return;
			}

			/* Because the window for IFRAMEs is the same as the outer
			 * document's window, we need to keep track of wether we
			 * have toggled the event handlers. Otherwise, they might
			 * get disabled and re-enabled immediately after.
			 */
			if (elementsWithToggledEventHandlers[elem]) {
				return;
			}

			elementsWithToggledEventHandlers[elem] = true;

			/* Toggle selected event handlers that have been set using
			 * "elem.oneventx = function () { … };"
			 */
			eventHandlerAttributesToToggle.forEach(function (attrib) {
				if (elem['jancss-' + attrib]) {
					elem[attrib] = elem['jancss-' + attrib];
					delete elem['jancss-' + attrib];
				} else if (elem[attrib]) {
					elem['jancss-' + attrib] = elem[attrib];
					elem[attrib] = function () { };
				}
			});

			/* Toggle all event handlers that have been set using jQuery. */
			if (typeof jQuery === 'function') {
				/* Since jQuery 1.7. */
				if (typeof jQuery.hasData === 'function' && jQuery.hasData(elem)) {
					/* Spotted in the wild: "jQuery._data is undefined". */
					if (typeof jQuery._data !== 'function') {
						return;
					}

					var data = jQuery._data(elem);
					if (data.jancssEvents) {
						data.events = data.jancssEvents;
						delete data.jancssEvents;

						jQuery._data(elem, data);

						return;
					} else if (data.events) {
						data.jancssEvents = data.events;
						delete data.events;

						jQuery._data(elem, data);

						return;
					}
				}


				/* Before jQuery 1.7 and after jQuery 1.2.3 */
				if (jQuery.fn.data) {
					var $elem = jQuery(elem);
					var eventsData = $elem.data('events');
					var jancssEventsData = $elem.data('jancssEvents');
					if (jancssEventsData) {
						$elem.data('events', jancssEventsData);
						$elem.removeData('jancssEvents');
					} else if (eventsData) {
						$elem.data('jancssEvents', eventsData);
						$elem.removeData('events');
					}
				}
			}
		});

		/* The code above does not work for event listeners added using
		 * addEventListener. Some sites listen for the "resize" event and
		 * then reposition elements by setting their style directly. To
		 * counteract this, simply delete all "style" attributes that get set
		 * while our style sheet is enabled. That'll show 'em!
		 */
		if (typeof MutationObserver === 'function' && !document.jancssHasMutationObserver) {
			document.jancssHasMutationObserver = true;
			var observer = new MutationObserver(function (mutations) {
				if (ourStyleSheet.disabled) {
					return;
				}

				mutations.forEach(function(mutation) {
					if (!mutation.target.hasAttribute('style') || mutation.target.id === 'xxxJanConsole' || mutation.target.xxxJanReadableAllowStyle) {
						return;
					}

					console.log('Readable++: removing "style" attribute set while in Readable++ mode on element ', mutation.target);
					mutation.target.removeAttribute(mutation.attributeName);
				});
			});

			observer.observe(document, {
				attributes: true,
				attributeFilter: ['style'],
				subtree: true
			});
		}

		/* Load bLazy.js "retina" images. This is more specific than the
		 * generic lazy-loading attributes below, and needs special handling
		 * because it specifies multiple sources in one attribute.
		 */
		toArray(document.querySelectorAll('img.b-lazy[data-src*="|"]')).forEach(function (img) {
			var attribute = 'data-src';
			var sources = img.getAttribute(attribute).split('|');
			img.src = sources.pop();
			img.removeAttribute(attribute);
		});

		/* Load Riloadr "<noscript>" images. This is more specific than the
		 * generic lazy-loading attributes below, and needs special handling
		 * because it would reset the images to blank when scrolling after
		 * Readable++ has been applied.
		 */
		toArray(document.querySelectorAll('img[data-src] + noscript')).forEach(function (noscript) {
			var img = noscript.previousElementSibling;

			var placeholder = img.previousElementSibling;
			if (placeholder && placeholder.tagName.toLowerCase() === 'svg') {
				placeholder.parentNode.removeChild(placeholder);
			}

			img.outerHTML = noscript.textContent;

			noscript.parentNode.removeChild(noscript);
		});

		/* Load images that are supposed to be loaded lazily. */
		[
			'data-original',
			'data-lazyload',
			'data-lazy-src',
			'data-full-src',
			'data-src'
		].forEach(function (attribute) {
			toArray(document.querySelectorAll('img[' + attribute + ']')).forEach(function (img) {
				img.src = img.getAttribute(attribute);
				img.removeAttribute(attribute);
			});
		});

		/* Show controls on AUDIO and VIDEO elements. */
		[].forEach.call(document.querySelectorAll('audio, video'), function (element) {
			element.controls = true;
		});

		/* Hide empty list items that are not ":empty" as per CSS. So,
		 * "empty" as in "containing text-less placeholders typically used
		 * for social sharing by showing an icon or logo or whatnot"
		 * (e.g. <li><a href="#"><span class="icon-fb"></span></a></li>).
		 */
		toArray(document.querySelectorAll('li :empty:not(img):not(input)')).forEach(function (elem) {
			while (elem.tagName && elem.tagName.toLowerCase() !== 'li') {
				elem = elem.parentNode;
			}

			if (elem.textContent.trim() === '' && !elem.querySelector('img, input'))
			{
				addClass(elem, 'jancss-emptyish');
			}
		});

		/* Remove known-bad elements. */
		toArray(document.querySelectorAll(elementsToRemoveSelectors.join(', '))).forEach(function (element) {
			element.parentNode.removeChild(element);
		});

		/* The first time this bookmarklet is called, add our style sheet and
		 * check for layout elements. */
		if (!ourStyleSheet) {
			(ourStyleSheet = document.createElementNS('http://www.w3.org/1999/xhtml', 'style')).id = 'jancss';
			ourStyleSheet.innerHTML = css;
			(document.head || document.body || document.documentElement).appendChild(ourStyleSheet);
			ourStyleSheet.disabled = true;

			/* Highlight matching data table columns on :hover. I do not
			 * know how to do this in pure CSS without COLGROUPs. */
			function columnMouseHandler(e) {
				if (!/^t[dh]$/i.test('' + e.target.tagName)) {
					return;
				}

				var targetCell = e.target, nthChild = targetCell.cellIndex + 1, table = targetCell.parentNode;
				while (table && table.tagName.toLowerCase() !== 'table') {
					table = table.parentNode;
				}

				var activeColumnClassName = 'jancss-active-col';
				toArray(table.querySelectorAll('td:nth-child(' + nthChild + ')')).forEach(function (cell) {
					if (e.type === 'mouseenter') {
						addClass(cell, activeColumnClassName);
					} else {
						removeClass(cell, activeColumnClassName);
					}
				});
			}

			/* Check which tables are used for data instead of layout. */
			toArray(document.querySelectorAll('table')).forEach(function (table) {
				var isTableForData = true;

				/* Are there any nested tables? */
				if (table.querySelector('table')) {
					var isWikipediaInfobox = (' ' + table.className + ' ').match(/infobox/);
					if (!isWikipediaInfobox) {
						console.log('Readable++: TABLE contains other TABLEs, so probably for layout: ', table);
						isTableForData = false;
					}
				}

				/* Are we in quirks mode and does this table takes up most of the page height? */
				else if (document.compatMode === 'BackCompat' && document.documentElement.scrollHeight > window.innerHeight && table.scrollHeight > 3/4 * document.documentElement.scrollHeight) {
					console.log('Readable++: TABLE seems pretty high in this document in quirks mode, so probably for layout: ', table);
					isTableForData = false;
				}

				/* If the table has several rows, look whether they are consistent in their number of cells. */
				else if (table.rows.length > 3) {
					var numCellsPerRow = [];
					toArray(table.rows).forEach(function (row) {
						if (numCellsPerRow.indexOf(row.cells.length) === -1) {
							numCellsPerRow.push(row.cells.length);
						}
					});

					/* Are we in quirks mode and does this table have at least three rows with a different number of cells? */
					if (document.compatMode === 'BackCompat' && numCellsPerRow.length >= 3) {
						console.log('Readable++: TABLE has a lot of differing cell counts in this document in quirks mode, so probably for layout: ', table);
						isTableForData = false;
					}

					/* Does this table only have rows with just a single column? */
					else if (numCellsPerRow.length === 1 && numCellsPerRow[0] === 1) {
						console.log('Readable++: TABLE has only rows of one cell each, so probably for layout: ', table);
						isTableForData = false;
					}
				}

				if (isTableForData) {
					addClass(table, 'jancss-probably-for-data');
					table.addEventListener('mouseenter', columnMouseHandler, true);
					table.addEventListener('mouseleave', columnMouseHandler, true);
				} else {
					addClass(table, 'jancss-probably-for-layout');
				}
			});

			/* (Re-)add some syntax highlighters' CSS if necessary. Those styles are often defined in the main CSS, so the HREF test in toggleStyles() does not match. */
			if (document.querySelector('.prettyprint')) {
				prettyPrintStyleSheet = document.createElementNS('http://www.w3.org/1999/xhtml', 'style');
				prettyPrintStyleSheet.textContent = '@import url(https://janmoesen.github.io/bookmarklets/css/prettify.css)';
				document.head.appendChild(prettyPrintStyleSheet);
			} else if (document.querySelector('.syntaxhighlighter')) {
				prettyPrintStyleSheet = document.createElementNS('http://www.w3.org/1999/xhtml', 'style');
				prettyPrintStyleSheet.textContent = '@import url(https://janmoesen.github.io/bookmarklets/css/syntaxhighlighter.css)';
				document.head.appendChild(prettyPrintStyleSheet);
			} else if (document.querySelector('.highlight .c, .highlight .k, .highlight .m, .highlight .s, .highlight .w')) {
				prettyPrintStyleSheet = document.createElementNS('http://www.w3.org/1999/xhtml', 'style');
				prettyPrintStyleSheet.textContent = '@import url(https://janmoesen.github.io/bookmarklets/css/pygments.css)';
				document.head.appendChild(prettyPrintStyleSheet);
			} else if (document.querySelector('code[class*="language-"] .token.punctuation')) {
				prettyPrintStyleSheet = document.createElementNS('http://www.w3.org/1999/xhtml', 'style');
				prettyPrintStyleSheet.textContent = '@import url(https://janmoesen.github.io/bookmarklets/css/prism.css)';
				document.head.appendChild(prettyPrintStyleSheet);
			}

			/* Add some classes to structure elements that have been used for layout. */
			structureElementsForLayoutSelectors.forEach(function (selector) {
				var xPathResult = document.evaluate(selector, document, null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);
				for (var i = 0; i < xPathResult.snapshotLength; i++) {
					var elem = xPathResult.snapshotItem(i);
					addClass(elem, 'jancss-probably-layout');
				}
			});

			/* Add some classes to layout elements that have been used for structure. */
			layoutElementsForStructureSelectors.forEach(function (selector) {
				toArray(document.querySelectorAll(selector)).forEach(function (elem) {
					if (elem.tagName.toLowerCase() !== 'b') {
						elem = elem.previousElementSibling;
					}

					addClass(elem, 'jancss-probably-structure');
				});
			});
		}

		/* Toggle between our readable and the page's original style sheet(s). */
		function toggleStyles() {
			ourStyleSheet.disabled = !ourStyleSheet.disabled;
			if (prettyPrintStyleSheet) {
				prettyPrintStyleSheet.disabled = ourStyleSheet.disabled;
			}
			allStyleSheets.forEach(function (styleSheet, i) {
				if (styleSheet.ownerNode !== ourStyleSheet && !syntaxHighlightHrefRegex.test(styleSheet.href)) {
					/* Remember whether this style sheet was originally disabled or not. We can't store on the CSSStyleSheet object, so use our DOM node. */
					if (ourStyleSheet['jancss-originally-disabled-' + i] === undefined) {
						ourStyleSheet['jancss-originally-disabled-' + i] = styleSheet.disabled;
					}

					if (ourStyleSheet.disabled) {
						/* Restore this style sheet's original state. */
						styleSheet.disabled = ourStyleSheet['jancss-originally-disabled-' + i];
					} else {
						/* Disable this style sheet when ours is enabled. */
						styleSheet.disabled = true;
						try {
							/* … unless it is a pretty-print style sheet. */
							if (styleSheet.cssRules[0] && styleSheet.cssRules[0].type === styleSheet.cssRules[0].IMPORT_RULE && styleSheet.cssRules[0].href) {
								styleSheet.disabled = !styleSheet.cssRules[0].href.match(/^https:\/\/janmoesen\.github\.io\//);
							}
						} catch (e) {
						}
					}
				}
			});

			/* Process all attributes for all elements. */
			all.forEach(function (elem, i) {
				attrs.forEach(function (attr, j) {
					/* Parse the attribute definition. Attributes can be restricted to certain elements, e.g. "table@width". */
					if (!(matches = attr.match(/([^@]+)@([^@]+)/)) || (elem.tagName && elem.tagName.toLowerCase() == matches[1])) {
						attr = matches ? matches[2] : attr;
						var names = { enabled: attr, disabled: 'jancss-' + attr };
						if (elem.hasAttribute(names.enabled)) {
							elem.setAttribute(names.disabled, elem.getAttribute(names.enabled));
							elem.removeAttribute(names.enabled);
						} else if (elem.hasAttribute(names.disabled)) {
							elem.setAttribute(names.enabled, elem.getAttribute(names.disabled));
							elem.removeAttribute(names.disabled);
						}
					}
				});
			});

			/* Restore the inline styles for certain code highlighters. */
			var disabledStyleAttr = 'jancss-style';
			toArray(document.querySelectorAll('.wp_syntax [' + disabledStyleAttr + ']')).forEach(function (elem) {
				elem.setAttribute('style', elem.getAttribute(disabledStyleAttr));
				elem.removeAttribute(disabledStyleAttr);
			});
		}

		/* Find the first thing that looks like the start of the actual content so we can scroll to it after applying our CSS. */
		function findContentElement() {
			/* When there seems to be a link to an in-page anchor (e.g. foo.html#mainContent), try to get the linked element. */
			if (location.hash) {
				var inPageAnchor, inPageAnchorSelectors = [
					'a[name="' + location.hash.substring(1) + '"]',
					location.hash.replace(/\./g, '\\.')
				];

				for (var i = 0; i < inPageAnchorSelectors.length; i++) {
					try {
						if ((inPageAnchor = document.querySelector(inPageAnchorSelectors[i]))) {
							console.log('Readable++: found in-page anchor based on location.hash: ', inPageAnchor);
							return inPageAnchor;
						}
					} catch (e) {
					}
				}
			}

			/* Check for headers whose text appears in the page title. */
			var headerInPageTitle;

			var charactersToIgnore = /[^A-Za-z\xAA\xB5\xBA\xC0-\xD6\xD8-\xF6\xF8-\u02C1\u02C6-\u02D1\u02E0-\u02E4\u02EC\u02EE\u0370-\u0374\u0376\u0377\u037A-\u037D\u037F\u0386\u0388-\u038A\u038C\u038E-\u03A1\u03A3-\u03F5\u03F7-\u0481\u048A-\u052F\u0531-\u0556\u0559\u0561-\u0587\u05D0-\u05EA\u05F0-\u05F2\u0620-\u064A\u066E\u066F\u0671-\u06D3\u06D5\u06E5\u06E6\u06EE\u06EF\u06FA-\u06FC\u06FF\u0710\u0712-\u072F\u074D-\u07A5\u07B1\u07CA-\u07EA\u07F4\u07F5\u07FA\u0800-\u0815\u081A\u0824\u0828\u0840-\u0858\u08A0-\u08B4\u0904-\u0939\u093D\u0950\u0958-\u0961\u0971-\u0980\u0985-\u098C\u098F\u0990\u0993-\u09A8\u09AA-\u09B0\u09B2\u09B6-\u09B9\u09BD\u09CE\u09DC\u09DD\u09DF-\u09E1\u09F0\u09F1\u0A05-\u0A0A\u0A0F\u0A10\u0A13-\u0A28\u0A2A-\u0A30\u0A32\u0A33\u0A35\u0A36\u0A38\u0A39\u0A59-\u0A5C\u0A5E\u0A72-\u0A74\u0A85-\u0A8D\u0A8F-\u0A91\u0A93-\u0AA8\u0AAA-\u0AB0\u0AB2\u0AB3\u0AB5-\u0AB9\u0ABD\u0AD0\u0AE0\u0AE1\u0AF9\u0B05-\u0B0C\u0B0F\u0B10\u0B13-\u0B28\u0B2A-\u0B30\u0B32\u0B33\u0B35-\u0B39\u0B3D\u0B5C\u0B5D\u0B5F-\u0B61\u0B71\u0B83\u0B85-\u0B8A\u0B8E-\u0B90\u0B92-\u0B95\u0B99\u0B9A\u0B9C\u0B9E\u0B9F\u0BA3\u0BA4\u0BA8-\u0BAA\u0BAE-\u0BB9\u0BD0\u0C05-\u0C0C\u0C0E-\u0C10\u0C12-\u0C28\u0C2A-\u0C39\u0C3D\u0C58-\u0C5A\u0C60\u0C61\u0C85-\u0C8C\u0C8E-\u0C90\u0C92-\u0CA8\u0CAA-\u0CB3\u0CB5-\u0CB9\u0CBD\u0CDE\u0CE0\u0CE1\u0CF1\u0CF2\u0D05-\u0D0C\u0D0E-\u0D10\u0D12-\u0D3A\u0D3D\u0D4E\u0D5F-\u0D61\u0D7A-\u0D7F\u0D85-\u0D96\u0D9A-\u0DB1\u0DB3-\u0DBB\u0DBD\u0DC0-\u0DC6\u0E01-\u0E30\u0E32\u0E33\u0E40-\u0E46\u0E81\u0E82\u0E84\u0E87\u0E88\u0E8A\u0E8D\u0E94-\u0E97\u0E99-\u0E9F\u0EA1-\u0EA3\u0EA5\u0EA7\u0EAA\u0EAB\u0EAD-\u0EB0\u0EB2\u0EB3\u0EBD\u0EC0-\u0EC4\u0EC6\u0EDC-\u0EDF\u0F00\u0F40-\u0F47\u0F49-\u0F6C\u0F88-\u0F8C\u1000-\u102A\u103F\u1050-\u1055\u105A-\u105D\u1061\u1065\u1066\u106E-\u1070\u1075-\u1081\u108E\u10A0-\u10C5\u10C7\u10CD\u10D0-\u10FA\u10FC-\u1248\u124A-\u124D\u1250-\u1256\u1258\u125A-\u125D\u1260-\u1288\u128A-\u128D\u1290-\u12B0\u12B2-\u12B5\u12B8-\u12BE\u12C0\u12C2-\u12C5\u12C8-\u12D6\u12D8-\u1310\u1312-\u1315\u1318-\u135A\u1380-\u138F\u13A0-\u13F5\u13F8-\u13FD\u1401-\u166C\u166F-\u167F\u1681-\u169A\u16A0-\u16EA\u16F1-\u16F8\u1700-\u170C\u170E-\u1711\u1720-\u1731\u1740-\u1751\u1760-\u176C\u176E-\u1770\u1780-\u17B3\u17D7\u17DC\u1820-\u1877\u1880-\u18A8\u18AA\u18B0-\u18F5\u1900-\u191E\u1950-\u196D\u1970-\u1974\u1980-\u19AB\u19B0-\u19C9\u1A00-\u1A16\u1A20-\u1A54\u1AA7\u1B05-\u1B33\u1B45-\u1B4B\u1B83-\u1BA0\u1BAE\u1BAF\u1BBA-\u1BE5\u1C00-\u1C23\u1C4D-\u1C4F\u1C5A-\u1C7D\u1CE9-\u1CEC\u1CEE-\u1CF1\u1CF5\u1CF6\u1D00-\u1DBF\u1E00-\u1F15\u1F18-\u1F1D\u1F20-\u1F45\u1F48-\u1F4D\u1F50-\u1F57\u1F59\u1F5B\u1F5D\u1F5F-\u1F7D\u1F80-\u1FB4\u1FB6-\u1FBC\u1FBE\u1FC2-\u1FC4\u1FC6-\u1FCC\u1FD0-\u1FD3\u1FD6-\u1FDB\u1FE0-\u1FEC\u1FF2-\u1FF4\u1FF6-\u1FFC\u2071\u207F\u2090-\u209C\u2102\u2107\u210A-\u2113\u2115\u2119-\u211D\u2124\u2126\u2128\u212A-\u212D\u212F-\u2139\u213C-\u213F\u2145-\u2149\u214E\u2183\u2184\u2C00-\u2C2E\u2C30-\u2C5E\u2C60-\u2CE4\u2CEB-\u2CEE\u2CF2\u2CF3\u2D00-\u2D25\u2D27\u2D2D\u2D30-\u2D67\u2D6F\u2D80-\u2D96\u2DA0-\u2DA6\u2DA8-\u2DAE\u2DB0-\u2DB6\u2DB8-\u2DBE\u2DC0-\u2DC6\u2DC8-\u2DCE\u2DD0-\u2DD6\u2DD8-\u2DDE\u2E2F\u3005\u3006\u3031-\u3035\u303B\u303C\u3041-\u3096\u309D-\u309F\u30A1-\u30FA\u30FC-\u30FF\u3105-\u312D\u3131-\u318E\u31A0-\u31BA\u31F0-\u31FF\u3400-\u4DB5\u4E00-\u9FD5\uA000-\uA48C\uA4D0-\uA4FD\uA500-\uA60C\uA610-\uA61F\uA62A\uA62B\uA640-\uA66E\uA67F-\uA69D\uA6A0-\uA6E5\uA717-\uA71F\uA722-\uA788\uA78B-\uA7AD\uA7B0-\uA7B7\uA7F7-\uA801\uA803-\uA805\uA807-\uA80A\uA80C-\uA822\uA840-\uA873\uA882-\uA8B3\uA8F2-\uA8F7\uA8FB\uA8FD\uA90A-\uA925\uA930-\uA946\uA960-\uA97C\uA984-\uA9B2\uA9CF\uA9E0-\uA9E4\uA9E6-\uA9EF\uA9FA-\uA9FE\uAA00-\uAA28\uAA40-\uAA42\uAA44-\uAA4B\uAA60-\uAA76\uAA7A\uAA7E-\uAAAF\uAAB1\uAAB5\uAAB6\uAAB9-\uAABD\uAAC0\uAAC2\uAADB-\uAADD\uAAE0-\uAAEA\uAAF2-\uAAF4\uAB01-\uAB06\uAB09-\uAB0E\uAB11-\uAB16\uAB20-\uAB26\uAB28-\uAB2E\uAB30-\uAB5A\uAB5C-\uAB65\uAB70-\uABE2\uAC00-\uD7A3\uD7B0-\uD7C6\uD7CB-\uD7FB\uF900-\uFA6D\uFA70-\uFAD9\uFB00-\uFB06\uFB13-\uFB17\uFB1D\uFB1F-\uFB28\uFB2A-\uFB36\uFB38-\uFB3C\uFB3E\uFB40\uFB41\uFB43\uFB44\uFB46-

			function normalizeText(str) {
				return str
					.replace(/\xAD/g, '')
					.replace(charactersToIgnore, ' ')
					.trim();
			}

			var metaTitleElement = document.querySelector('meta[property="og:title"], meta[property="twitter:title"], meta[name="title"]');
			var normalizedMetaTitle = metaTitleElement && normalizeText(metaTitleElement.content);
			var normalizedPageTitle = normalizeText(document.title);

			headerSelectors.forEach(function (selector) {
				toArray(document.querySelectorAll(selector)).forEach(function (element) {
					var normalizedText = normalizeText(element.textContent);

					/* Make sure the element has text. */
					if (!normalizedText.length) {
						return;
					}

					/* Make sure the element is visible. */
					var boundingRect = element.getBoundingClientRect();
					if (!boundingRect.width || !boundingRect.height) {
						return;
					}

					/* Make sure the element is "above the fold" (or near it). Some sites use
					 * bigger headings for a footer section than for the actual content, but in
					 * general, the real header should be visible within the first screenful. */
					if (boundingRect.top + window.scrollY > window.innerHeight * 1.5) {
						return;
					}

					/* Make sure the title can contain the element's text. */
					if (
						normalizedPageTitle.length < normalizedText.length
						&& (!metaTitleElement || normalizedMetaTitle.length < normalizedText.length)
					) {
						return;
					}

					/* See if the element's text appears in the page title. */
					var substringIndex = normalizedPageTitle.indexOf(normalizedText);

					if (substringIndex === -1 && metaTitleElement) {
						substringIndex = normalizedMetaTitle.indexOf(normalizedText);
					}

					if (substringIndex === -1) {
						return;
					}

					/* Make sure the element is not contained in an ASIDE or a sidebar (e.g. in a list of articles). */
					if (typeof element.closest === 'function' && element.closest(ancestorsForHeadersToIgnoreSelectors.join(', '))) {
						return;
					}

					headerInPageTitle = element;
				});
			});

			if (headerInPageTitle) {
				console.log('Readable++: found suitable header element whose text appears in the page title: ', headerInPageTitle);
				return headerInPageTitle;
			}

			/* Fall back to common content element selectors. */
			for (var i = 0; i < contentSelectors.length; i++) {
				try {
					var element = document.querySelector(contentSelectors[i]);

					/* Make sure the element was either an anchor or something "visible". */
					if (element && (element.tagName.toLowerCase() === 'a' || element.offsetWidth || element.offsetHeight)) {
						console.log('Readable++: found matching selector for content element: ' + contentSelectors[i] + '\nElement: ', element);
						return element;
					}
				}
				catch (e) {
					console.log('Readable++: bad selector for content element: ' + contentSelectors[i] + '\nException: ' + e);
				}
			}
		}

		/* Check if there is an element that we should scroll into view so we can immediately start reading. */
		var contentElement, shouldScrollContentIntoView = false;
		var selection = document.getSelection && document.getSelection();
		if (selection && selection.anchorNode && (selection + '').length) {
			/* If the user has created a selection, scroll the element containing that selection into view. (I often triple-click a paragraph to select it before reading.) */
			shouldScrollContentIntoView = true;
			contentElement = selection.anchorNode;
			while (contentElement.nodeType !== contentElement.ELEMENT_NODE && contentElement.parentNode) {
				contentElement = contentElement.parentNode;
			}

			console.log('Readable++: found selected element to scroll into view: ', contentElement);
		} else if (ourStyleSheet.disabled && (contentElement = findContentElement())) {
			/* When switching from the original style sheet to ours, scroll to the start of the content, unless the user had scrolled already. */
			var tmpElement = contentElement, contentTop = 0;
			do {
				contentTop += tmpElement.offsetTop;
			} while ((tmpElement = tmpElement.offsetParent));

			shouldScrollContentIntoView = !window.scrollY || Math.abs(window.scrollY - contentTop) < 20;
		}

		/* Finally, toggle the style sheets. */
		toggleStyles();

		/* Scroll to the start of the content if we found it and have not scrolled yet. */
		shouldScrollContentIntoView && contentElements.push(contentElement);

		/* Recurse for frames and iframes. */
		try {
			toArray(document.querySelectorAll('frame, iframe, object[type^="text/html"], object[type^="application/xhtml+xml"]')).forEach(function (elem) {
				execute(elem.contentDocument);
			});
		} catch (e) {
			/* Catch exceptions for out-of-domain access, but do not do anything with them. */
		}
	})(document);

	/* When there are IFRAMEs etc. with their own main content element,
	 * scrolling them into view as soon as they are found would override the
	 * main document’s scroll position. By scrolling the nested elements into
	 * view *first*, and the main document’s main content element *last*,
	 * things behave more as expected.
	 */
	var contentElement;
	while ((contentElement = contentElements.pop())) {
		contentElement.scrollIntoView({
			behavior: 'smooth',
			block: 'start',
			inline: 'start'
		});
	};
})();