☰

SE Preview on hover

Shows preview of the linked questions/answers on hover

目前为 2021-07-09 提交的版本。查看 最新版本。

  1. // ==UserScript==
  2. // @name           SE Preview on hover
  3. // @description    Shows preview of the linked questions/answers on hover
  4. // @version        1.1.4
  5. // @author         wOxxOm
  6. // @namespace      wOxxOm.scripts
  7. // @license        MIT License
  8. //
  9. // please use only matches for the previewable targets and make sure the domain
  10. // is extractable via [-.\w] so that it starts with . like .stackoverflow.com
  11. // @match          *://*.stackoverflow.com/*
  12. // @match          *://*.superuser.com/*
  13. // @match          *://*.serverfault.com/*
  14. // @match          *://*.askubuntu.com/*
  15. // @match          *://*.stackapps.com/*
  16. // @match          *://*.mathoverflow.net/*
  17. // @match          *://*.stackexchange.com/*
  18. //
  19. // please use only includes for the container sites
  20. // @include        *://www.google.com/search*/
  21. // @include        /https?:\/\/(www\.)?google(\.com?)?(\.\w\w)?\/(webhp|q|.*?[?#]q=|search).*/
  22. // @include        *://*.bing.com/*
  23. // @include        *://*.yahoo.com/*
  24. // @include        /https?:\/\/(\w+\.)*yahoo.(com|\w\w(\.\w\w)?)\/.*/
  25. //
  26. // @require        https://greasyfork.org/scripts/27531/code/LZStringUnsafe.js
  27. // @require        https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/highlight.min.js
  28. // @require        https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/languages/autohotkey.min.js
  29. // @require        https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/languages/autoit.min.js
  30. // @require        https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/languages/dart.min.js
  31. // @require        https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/languages/delphi.min.js
  32. // @require        https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/languages/haskell.min.js
  33. // @require        https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/languages/moonscript.min.js
  34. // @require        https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/languages/nsis.min.js
  35. // @require        https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/languages/powershell.min.js
  36. // @require        https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/languages/r.min.js
  37. // @require        https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/languages/vbnet.min.js
  38. // @require        https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/languages/vbscript-html.min.js
  39. // @require        https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/languages/vbscript.min.js
  40. // @require        https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/languages/x86asm.min.js
  41. // @resource       HL-style https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/styles/default.min.css
  42. // @resource       HL-style-dark https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.2.0/styles/atom-one-dark-reasonable.min.css
  43. //
  44. // @grant          GM_addStyle
  45. // @grant          GM_xmlhttpRequest
  46. // @grant          GM_getValue
  47. // @grant          GM_setValue
  48. // @grant          GM_getResourceText
  49. //
  50. // @connect        stackoverflow.com
  51. // @connect        superuser.com
  52. // @connect        serverfault.com
  53. // @connect        askubuntu.com
  54. // @connect        stackapps.com
  55. // @connect        mathoverflow.net
  56. // @connect        stackexchange.com
  57. // @connect        sstatic.net
  58. // @connect        gravatar.com
  59. // @connect        imgur.com
  60. // @connect        self
  61. //
  62. // @noframes
  63. // @run-at         document-idle
  64. // ==/UserScript==
  65.  
  66. /* global hljs LZStringUnsafe */
  67. 'use strict';
  68.  
  69. Promise.resolve().then(() => {
  70.   Detector.init();
  71.   Security.init();
  72.   Urler.init();
  73.   Cache.init();
  74. });
  75.  
  76. const PREVIEW_DELAY = 200;
  77. const AUTOHIDE_DELAY = 1000;
  78. const BUSY_CURSOR_DELAY = 300;
  79. // 1 minute for the recently active posts, scales up logarithmically
  80. const CACHE_DURATION = 60e3;
  81.  
  82. const PADDING = 24;
  83. const PROSE_WIDTH = 660; // .s-prose selector
  84. const PROSE_MARGIN = 16; // .s-prose margin-right
  85. const WIDTH = PROSE_WIDTH + PADDING * 2;
  86. const BORDER = 8;
  87. const TOP_BORDER = 24;
  88. const MIN_HEIGHT = 200;
  89. let colors;
  90. const COLORS_LIGHT = {
  91.   body: {
  92.     back: '#ffffff',
  93.     fore: '#000000',
  94.   },
  95.   question: {
  96.     back: '#5894d8',
  97.     fore: '#265184',
  98.     foreInv: '#fff',
  99.   },
  100.   answer: {
  101.     back: '#70c350',
  102.     fore: '#3f7722',
  103.     foreInv: '#fff',
  104.   },
  105.   deleted: {
  106.     back: '#cd9898',
  107.     fore: '#b56767',
  108.     foreInv: '#fff',
  109.   },
  110.   closed: {
  111.     back: '#ffce5d',
  112.     fore: '#c28800',
  113.     foreInv: '#fff',
  114.   },
  115. };
  116. const COLORS_DARK = {
  117.   body: {
  118.     back: '#222222',
  119.     fore: '#cccccc',
  120.   },
  121.   question: {
  122.     back: '#004696',
  123.     fore: '#6abaff',
  124.     foreInv: '#004696',
  125.   },
  126.   answer: {
  127.     back: '#004c1b',
  128.     fore: '#39c466',
  129.     foreInv: '#004c1b',
  130.   },
  131.   deleted: {
  132.     back: '#4d0a0b',
  133.     fore: '#b56767',
  134.     foreInv: '#fff',
  135.   },
  136.   closed: {
  137.     back: '#4b360a',
  138.     fore: '#c28800',
  139.     foreInv: '#fff',
  140.   },
  141. };
  142. const ID = 'SEpreview';
  143. const EXPANDO = Symbol(ID);
  144.  
  145. const pv = {
  146.   /** @type {Target} */
  147.   target: null,
  148.   /** @type {Element} */
  149.   _frame: null,
  150.   /** @type {Element} */
  151.   get frame() {
  152.     if (!this._frame)
  153.       Preview.init();
  154.     if (!document.contains(this._frame))
  155.       document.body.appendChild(this._frame);
  156.     return this._frame;
  157.   },
  158.   set frame(element) {
  159.     this._frame = element;
  160.     return element;
  161.   },
  162.   /** @type {Post} */
  163.   post: {},
  164.   hover: {x: 0, y: 0},
  165.   stylesOverride: '',
  166. };
  167.  
  168. class Detector {
  169.  
  170.   static init() {
  171.     const sites = GM_info.script.matches.map(m => m.match(/[-.\w]+/)[0]);
  172.     const rxsSites = 'https?://(\\w*\\.)*(' +
  173.       GM_info.script.matches
  174.         .map(m => m.match(/^.*?\/\/\W*(\w.*?)\//)[1].replace(/\./g, '\\.'))
  175.         .join('|') +
  176.       ')/';
  177.     Detector.rxPreviewableSite = new RegExp(rxsSites);
  178.     Detector.rxPreviewablePost = new RegExp(rxsSites + '(questions|q|a|posts/comments)/\\d+');
  179.     Detector.pageUrls = getBaseUrls(location, Detector.rxPreviewablePost);
  180.     Detector.isStackExchangePage = Detector.rxPreviewableSite.test(location);
  181.  
  182.     const {
  183.       rxPreviewablePost,
  184.       isStackExchangePage: isSE,
  185.       pageUrls: {base, baseShort},
  186.     } = Detector;
  187.  
  188.     // array of target elements accumulated in mutation observer
  189.     // cleared in attachHoverListener
  190.     const moQueue = [];
  191.  
  192.     onMutation([{
  193.       addedNodes: [document.body],
  194.     }]);
  195.  
  196.     new MutationObserver(onMutation)
  197.       .observe(document.body, {
  198.         childList: true,
  199.         subtree: true,
  200.       });
  201.  
  202.     Detector.init = true;
  203.  
  204.     function onMutation(mutations) {
  205.       const alreadyScheduled = moQueue.length > 0;
  206.       for (const {addedNodes} of mutations) {
  207.         for (const n of addedNodes) {
  208.           if (!n.localName)
  209.             continue;
  210.           if (n.localName === 'a') {
  211.             moQueue.push(n);
  212.             continue;
  213.           }
  214.           // not using ..spreading since there could be 100k links for all we know
  215.           // and that might exceed JS engine stack limit which can be pretty low
  216.           const targets = n.getElementsByTagName('a');
  217.           for (let k = 0, len = targets.length; k < len; k++)
  218.             moQueue.push(targets[k]);
  219.           if (!isSE)
  220.             continue;
  221.           if (n.classList.contains('question-summary')) {
  222.             moQueue.push(...n.getElementsByClassName('answered'));
  223.             moQueue.push(...n.getElementsByClassName('answered-accepted'));
  224.             continue;
  225.           }
  226.           for (const el of n.getElementsByClassName('question-summary')) {
  227.             moQueue.push(...el.getElementsByClassName('answered'));
  228.             moQueue.push(...el.getElementsByClassName('answered-accepted'));
  229.           }
  230.         }
  231.       }
  232.       if (!alreadyScheduled && moQueue.length)
  233.         setTimeout(hoverize);
  234.     }
  235.  
  236.     function hoverize() {
  237.       for (const el of moQueue) {
  238.         if (el[EXPANDO] instanceof Target)
  239.           continue;
  240.         if (el.localName === 'a') {
  241.           if (isSE && el.classList.contains('js-share-link'))
  242.             continue;
  243.           const previewable = isPreviewable(el) || !isSE && isEmbeddedUrlPreviewable(el);
  244.           if (!previewable)
  245.             continue;
  246.           const url = Urler.makeHttps(el.href);
  247.           if (url.startsWith(base) || url.startsWith(baseShort))
  248.             continue;
  249.         }
  250.         Target.createHoverable(el);
  251.       }
  252.       moQueue.length = 0;
  253.     }
  254.  
  255.     function isPreviewable(a) {
  256.       let href = false;
  257.       const host = '.' + a.hostname;
  258.       const hostLen = host.length;
  259.       for (const stackSite of sites) {
  260.         if (host[hostLen - stackSite.length] === '.' &&
  261.             host.endsWith(stackSite) &&
  262.             rxPreviewablePost.test(href || (href = a.href)))
  263.           return true;
  264.       }
  265.     }
  266.  
  267.     function isEmbeddedUrlPreviewable(a) {
  268.       const url = a.href;
  269.       let i = url.indexOf('http', 1);
  270.       if (i < 0)
  271.         return false;
  272.       i = (
  273.         url.indexOf('http://', i) + 1 ||
  274.         url.indexOf('https://', i) + 1 ||
  275.         url.indexOf('http%3A%2F%2F', i) + 1 ||
  276.         url.indexOf('https%3A%2F%2F', i) + 1
  277.       ) - 1;
  278.       if (i < 0)
  279.         return false;
  280.       const j = url.indexOf('&', i);
  281.       const embeddedUrl = url.slice(i, j > 0 ? j : undefined);
  282.       return rxPreviewablePost.test(embeddedUrl);
  283.     }
  284.  
  285.     function getBaseUrls(url, rx) {
  286.       if (!rx.test(url))
  287.         return {};
  288.       const base = Urler.makeHttps(RegExp.lastMatch);
  289.       return {
  290.         base,
  291.         baseShort: base.replace('/questions/', '/q/'),
  292.       };
  293.     }
  294.   }
  295. }
  296.  
  297. /**
  298.  * @property {Element} element
  299.  * @property {Boolean} isLink
  300.  * @property {String}  url
  301.  * @property {Number}  timer
  302.  * @property {Number}  timerCursor
  303.  * @property {String}  savedCursor
  304.  */
  305. class Target {
  306.  
  307.   /** @param {Element} el */
  308.   static createHoverable(el) {
  309.     const target = new Target(el);
  310.     Object.defineProperty(el, EXPANDO, {value: target});
  311.     el.removeAttribute('title');
  312.     el.addEventListener('mouseover', Target._onMouseOver);
  313.     return target;
  314.   }
  315.  
  316.   /** @param {Element} el */
  317.   constructor(el) {
  318.     this.element = el;
  319.     this.isLink = el.localName === 'a';
  320.   }
  321.  
  322.   release() {
  323.     $.off('mousemove', this.element, Target._onMove);
  324.     $.off('mouseout', this.element, Target._onHoverEnd);
  325.     $.off('mousedown', this.element, Target._onHoverEnd);
  326.  
  327.     for (const k in this) {
  328.       if (k.startsWith('timer') && this[k] >= 1) {
  329.         clearTimeout(this[k]);
  330.         this[k] = 0;
  331.       }
  332.     }
  333.     BusyCursor.hide(this);
  334.     pv.target = null;
  335.   }
  336.  
  337.   get url() {
  338.     const el = this.element;
  339.     if (this.isLink)
  340.       return el.href;
  341.     const a = $('a', el.closest('.question-summary'));
  342.     if (a)
  343.       return a.href;
  344.   }
  345.  
  346.   /** @param {MouseEvent} e */
  347.   static _onMouseOver(e) {
  348.     if (Util.hasKeyModifiers(e))
  349.       return;
  350.     const self = /** @type {Target} */ this[EXPANDO];
  351.     if (self === Preview.target && Preview.shown() ||
  352.         self === pv.target)
  353.       return;
  354.  
  355.     if (pv.target)
  356.       pv.target.release();
  357.     pv.target = self;
  358.  
  359.     pv.hover.x = e.pageX;
  360.     pv.hover.y = e.pageY;
  361.  
  362.     $.on('mousemove', this, Target._onMove);
  363.     $.on('mouseout', this, Target._onHoverEnd);
  364.     $.on('mousedown', this, Target._onHoverEnd);
  365.  
  366.     Target._restartTimer(self);
  367.   }
  368.  
  369.   /** @param {MouseEvent} e */
  370.   static _onHoverEnd(e) {
  371.     if (e.type === 'mouseout' && e.target !== this)
  372.       return;
  373.     const self = /** @type {Target} */ this[EXPANDO];
  374.     if (pv.xhr && pv.target === self) {
  375.       pv.xhr.abort();
  376.       pv.xhr = null;
  377.     }
  378.     self.release();
  379.     self.timer = setTimeout(Target._onAbortTimer, AUTOHIDE_DELAY, self);
  380.   }
  381.  
  382.   /** @param {MouseEvent} e */
  383.   static _onMove(e) {
  384.     const stoppedMoving =
  385.       Math.abs(pv.hover.x - e.pageX) < 2 &&
  386.       Math.abs(pv.hover.y - e.pageY) < 2;
  387.     if (stoppedMoving) {
  388.       pv.hover.x = e.pageX;
  389.       pv.hover.y = e.pageY;
  390.       Target._restartTimer(this[EXPANDO]);
  391.     }
  392.   }
  393.  
  394.   /** @param {Target} self */
  395.   static _restartTimer(self) {
  396.     if (self.timer)
  397.       clearTimeout(self.timer);
  398.     self.timer = setTimeout(Target._onTimer, PREVIEW_DELAY, self);
  399.   }
  400.  
  401.   /** @param {Target} self */
  402.   static _onTimer(self) {
  403.     self.timer = 0;
  404.     const el = self.element;
  405.     if (!el.matches(':hover')) {
  406.       self.release();
  407.       return;
  408.     }
  409.     $.off('mousemove', el, Target._onMove);
  410.  
  411.     if (self.url)
  412.       Preview.start(self);
  413.   }
  414.  
  415.   /** @param {Target} self */
  416.   static _onAbortTimer(self) {
  417.     if ((self === pv.target || self === Preview.target) &&
  418.         pv.frame && !pv.frame.matches(':hover')) {
  419.       pv.target = null;
  420.       Preview.hide({fade: true});
  421.     }
  422.   }
  423. }
  424.  
  425.  
  426. class BusyCursor {
  427.  
  428.   /** @param {Target} target */
  429.   static schedule(target) {
  430.     target.timerCursor = setTimeout(BusyCursor._onTimer, BUSY_CURSOR_DELAY, target);
  431.   }
  432.  
  433.   /** @param {Target} target */
  434.   static hide(target) {
  435.     if (target.timerCursor) {
  436.       clearTimeout(target.timerCursor);
  437.       target.timerCursor = 0;
  438.     }
  439.     const style = target.element.style;
  440.     if (style.cursor === 'wait')
  441.       style.cursor = target.savedCursor;
  442.   }
  443.  
  444.   /** @param {Target} target */
  445.   static _onTimer(target) {
  446.     target.timerCursor = 0;
  447.     target.savedCursor = target.element.style.cursor;
  448.     $.setStyle(target.element, ['cursor', 'wait']);
  449.   }
  450. }
  451.  
  452.  
  453. class Preview {
  454.  
  455.   static init() {
  456.     pv.frame = $.create(`#${ID}`, {parent: document.body});
  457.     pv.shadow = pv.frame.attachShadow({mode: 'open'});
  458.     pv.body = $.create(`body#${ID}-body`, {parent: pv.shadow});
  459.  
  460.     const WRAP_AROUND = '(or wrap around to the question)';
  461.     const TITLE_PREV = 'Previous answer\n' + WRAP_AROUND;
  462.     const TITLE_NEXT = 'Next answer\n' + WRAP_AROUND;
  463.     const TITLE_ENTER = 'Return to the question\n(Enter was Return initially)';
  464.  
  465.     pv.answersTitle =
  466.       $.create(`#${ID}-answers-title`, [
  467.         'Answers:',
  468.         $.create('p', [
  469.           'Use ',
  470.           $.create('b', {title: TITLE_PREV}),
  471.           $.create('b', {title: TITLE_NEXT, attributes: {mirrored: ''}}),
  472.           $.create('label', {title: TITLE_ENTER}, 'Enter'),
  473.           ' to switch entries',
  474.         ]),
  475.       ]);
  476.  
  477.     $.on('keydown', pv.frame, Preview.onKey);
  478.     $.on('keyup', pv.frame, Util.consumeEsc);
  479.  
  480.     $.on('mouseover', pv.body, ScrollLock.enable);
  481.     $.on('click', pv.body, Preview.onClick);
  482.  
  483.     Sizer.init();
  484.     Styles.init();
  485.     Preview.init = true;
  486.   }
  487.  
  488.   /** @param {Target} target */
  489.   static async start(target) {
  490.     Preview.target = target;
  491.  
  492.     if (!Security.checked)
  493.       Security.check();
  494.  
  495.     const {url} = target;
  496.  
  497.     let data = Cache.read(url);
  498.     if (data) {
  499.       const r = await Urler.get(url, {method: 'HEAD'});
  500.       const postTime = Util.getResponseDate(r.responseHeaders);
  501.       if (postTime >= data.time)
  502.         data = null;
  503.     }
  504.  
  505.     if (!data) {
  506.       BusyCursor.schedule(target);
  507.       const {finalUrl, responseText: html} = await Urler.get(target.url);
  508.       data = {finalUrl, html, unsaved: true};
  509.       BusyCursor.hide(target);
  510.     }
  511.  
  512.     data.url = url;
  513.     data.showAnswer = !target.isLink;
  514.  
  515.     if (!Preview.prepare(data))
  516.       Preview.target = null;
  517.     else if (data.unsaved && data.lastActivity >= 1)
  518.       Preview.save(data);
  519.   }
  520.  
  521.   static save({url, finalUrl, html, lastActivity}) {
  522.     const inactiveDays = Math.max(0, (Date.now() - lastActivity) / (24 * 3600e3));
  523.     const cacheDuration = CACHE_DURATION * Math.pow(Math.log(inactiveDays + 1) + 1, 2);
  524.     setTimeout(Cache.write, 1000, {url, finalUrl, html, cacheDuration});
  525.   }
  526.  
  527.   // data is mutated: its lastActivity property is assigned!
  528.   static prepare(data) {
  529.     const {finalUrl, html, showAnswer, doc = Util.parseHtml(html)} = data;
  530.  
  531.     if (!doc || !doc.head)
  532.       return Util.error('no HEAD in the document received for', finalUrl);
  533.  
  534.     if (!$('base', doc))
  535.       $.create('base', {href: finalUrl, parent: doc.head});
  536.  
  537.     let answerId;
  538.     if (showAnswer) {
  539.       const el = $('[id^="answer-"]', doc);
  540.       answerId = el && el.id.match(/\d+/)[0];
  541.     } else {
  542.       answerId = finalUrl.match(/questions\/\d+\/[^/]+\/(\d+)|$/)[1];
  543.     }
  544.     const selector = answerId ? '#answer-' + answerId : '#question';
  545.     const core = $(`${selector} .${answerId ? 'answer' : 'post'}cell`, doc);
  546.     if (!core)
  547.       return Util.error('No parsable post found', doc);
  548.  
  549.     const isQuestion = !answerId;
  550.     const status = isQuestion && $('[role="status"]', core);
  551.     const isClosed = status && $('[href*="closed"]', status);
  552.     const isDeleted = Boolean(core.closest('.deleted-answer'));
  553.     const type = [
  554.       isQuestion && 'question' || 'answer',
  555.       isDeleted && 'deleted',
  556.       isClosed && 'closed',
  557.     ].filter(Boolean).join(' ');
  558.     const answers = $.all('.answer', doc);
  559.     const comments = $(`${selector} .comments`, doc);
  560.     const commentsParent = comments.parentElement;
  561.     const showMoreComments = $(`${selector} .js-show-link.comments-link`, doc);
  562.     const lastActivity = Util.tryCatch(Util.extractTime, $('a[href*="?lastactivity"]', core)) ||
  563.                          Date.now();
  564.     Object.assign(pv, {
  565.       finalUrl,
  566.       finalUrlOfQuestion: Urler.makeCacheable(finalUrl),
  567.     });
  568.     /** @typedef Post
  569.      * @property {Document}  doc
  570.      * @property {String}    html
  571.      * @property {String}    selector
  572.      * @property {String}    type
  573.      * @property {String}    id
  574.      * @property {String}    title
  575.      * @property {Boolean}   isQuestion
  576.      * @property {Boolean}   isDeleted
  577.      * @property {Number}    lastActivity
  578.      * @property {Number}    numAnswers
  579.      * @property {Element}   core
  580.      * @property {Element}   comments
  581.      * @property {Element[]} answers
  582.      * @property {Element[]} renderParts
  583.      */
  584.     Object.assign(pv.post, {
  585.       doc,
  586.       html,
  587.       core,
  588.       selector,
  589.       answers,
  590.       comments,
  591.       type,
  592.       isQuestion,
  593.       isDeleted,
  594.       lastActivity,
  595.       id: isQuestion ? Urler.getFirstNumber(finalUrl) : answerId,
  596.       title: $('meta[property="og:title"]', doc).content,
  597.       numAnswers: answers.length,
  598.       renderParts: [
  599.         // including the parent so the right CSS kicks in
  600.         core,
  601.         commentsParent,
  602.       ],
  603.     });
  604.  
  605.     $.remove('script', doc);
  606.     // remove the comment actions block
  607.     $.remove('.comment-form, [id^="comments-link-"], .hover-only-label', commentsParent);
  608.     if (!commentsParent.contains(showMoreComments))
  609.       commentsParent.appendChild(showMoreComments);
  610.  
  611.     Promise.all([
  612.       pv.frame,
  613.       Preview.addStyles(),
  614.       Security.ready(),
  615.     ]).then(Preview.show);
  616.  
  617.     data.lastActivity = lastActivity;
  618.     return true;
  619.   }
  620.  
  621.   static show() {
  622.     Render.all();
  623.  
  624.     const style = getComputedStyle(pv.frame);
  625.     if (style.opacity !== '1' || style.display !== 'block') {
  626.       $.setStyle(pv.frame, ['display', 'block']);
  627.       setTimeout($.setStyle, 0, pv.frame, ['opacity', '1']);
  628.     }
  629.  
  630.     pv.parts.focus();
  631.   }
  632.  
  633.   static hide({fade = false} = {}) {
  634.     if (Preview.target) {
  635.       Preview.target.release();
  636.       Preview.target = null;
  637.     }
  638.  
  639.     pv.body.onmouseover = null;
  640.     pv.body.onclick = null;
  641.     pv.body.onkeydown = null;
  642.  
  643.     if (fade) {
  644.       Util.fadeOut(pv.frame)
  645.         .then(Preview.eraseBoxIfHidden);
  646.     } else {
  647.       $.setStyle(pv.frame,
  648.         ['opacity', '0'],
  649.         ['display', 'none']);
  650.       Preview.eraseBoxIfHidden();
  651.     }
  652.   }
  653.  
  654.   static shown() {
  655.     return pv.frame.style.opacity === '1';
  656.   }
  657.  
  658.   /** @param {KeyboardEvent} e */
  659.   static onKey(e) {
  660.     switch (e.key) {
  661.       case 'Escape':
  662.         Preview.hide({fade: true});
  663.         break;
  664.       case 'ArrowUp':
  665.       case 'PageUp':
  666.         if (pv.parts.scrollTop)
  667.           return;
  668.         break;
  669.       case 'ArrowDown':
  670.       case 'PageDown': {
  671.         const {scrollTop: t, clientHeight: h, scrollHeight} = pv.parts;
  672.         if (t + h < scrollHeight)
  673.           return;
  674.         break;
  675.       }
  676.       case 'ArrowLeft':
  677.       case 'ArrowRight': {
  678.         if (!pv.post.numAnswers)
  679.           return;
  680.         // current is 0 if isQuestion, 1 is the first answer
  681.         const answers = $.all(`#${ID}-answers a`);
  682.         const current = pv.post.numAnswers ?
  683.           answers.indexOf($('.SEpreviewed')) + 1 :
  684.           pv.post.isQuestion ? 0 : 1;
  685.         const num = pv.post.numAnswers + 1;
  686.         const dir = e.key === 'ArrowLeft' ? -1 : 1;
  687.         const toShow = (current + dir + num) % num;
  688.         const a = toShow ? answers[toShow - 1] : $(`#${ID}-title`);
  689.         a.click();
  690.         break;
  691.       }
  692.       case 'Enter':
  693.         if (pv.post.isQuestion)
  694.           return;
  695.         $(`#${ID}-title`).click();
  696.         break;
  697.       default:
  698.         return;
  699.     }
  700.     e.preventDefault();
  701.   }
  702.  
  703.   /** @param {MouseEvent} e */
  704.   static onClick(e) {
  705.     if (e.target.id === `${ID}-close`) {
  706.       Preview.hide();
  707.       return;
  708.     }
  709.  
  710.     const link = e.target.closest('a');
  711.     if (!link)
  712.       return;
  713.  
  714.     if (link.matches('.js-show-link.comments-link')) {
  715.       Util.fadeOut(link, 0.5);
  716.       Preview.loadComments();
  717.       e.preventDefault();
  718.       return;
  719.     }
  720.  
  721.     if (e.button ||
  722.         Util.hasKeyModifiers(e) ||
  723.         !link.matches('.SEpreviewable')) {
  724.       link.target = '_blank';
  725.       return;
  726.     }
  727.  
  728.     e.preventDefault();
  729.  
  730.     const {doc} = pv.post;
  731.     if (link.id === `${ID}-title`)
  732.       Preview.prepare({doc, finalUrl: pv.finalUrlOfQuestion});
  733.     else if (link.matches(`#${ID}-answers a`))
  734.       Preview.prepare({doc, finalUrl: pv.finalUrlOfQuestion + '/' + Urler.getFirstNumber(link)});
  735.     else
  736.       Preview.start(new Target(link));
  737.   }
  738.  
  739.   static eraseBoxIfHidden() {
  740.     if (!Preview.shown())
  741.       pv.body.textContent = '';
  742.   }
  743.  
  744.   static setHeight(height) {
  745.     const currentHeight = pv.frame.clientHeight;
  746.     const borderHeight = pv.frame.offsetHeight - currentHeight;
  747.     const newHeight = Math.max(MIN_HEIGHT, Math.min(innerHeight - borderHeight, height));
  748.     if (newHeight !== currentHeight)
  749.       $.setStyle(pv.frame, ['height', newHeight + 'px']);
  750.   }
  751.  
  752.   static async addStyles() {
  753.     const isDark = matchMedia('(prefers-color-scheme: dark)').matches;
  754.     colors = isDark ? COLORS_DARK : COLORS_LIGHT;
  755.     pv.body.className = isDark ? 'theme-dark' : '';
  756.     Styles.init(isDark);
  757.  
  758.     let last = $.create(`style#${ID}-styles.${Styles.REUSABLE}`, {
  759.       textContent: pv.stylesOverride,
  760.       before: pv.shadow.firstChild,
  761.     });
  762.  
  763.     if (!pv.styles) {
  764.       pv.styles = new Map();
  765.       pv.stylesScaled = new Set();
  766.     }
  767.  
  768.     const toDownload = [];
  769.     const sourceElements = $.all('link[rel="stylesheet"], style', pv.post.doc);
  770.  
  771.     for (const {href, textContent, localName} of sourceElements) {
  772.       const isLink = localName === 'link';
  773.       const id = ID + '-style-' + (isLink ? href : await Util.sha256(textContent));
  774.       const el = pv.styles.get(id);
  775.       if (!el && isLink)
  776.         toDownload.push(Urler.get({url: href, context: id}));
  777.       last = $.create('style', {
  778.         id,
  779.         className: Styles.REUSABLE,
  780.         textContent: isLink ? $.text(el) : textContent,
  781.         after: last,
  782.       });
  783.       pv.styles.set(id, last);
  784.     }
  785.  
  786.     const downloaded = await Promise.all(toDownload);
  787.  
  788.     for (const {responseText, context: id} of downloaded)
  789.       Styles.applyRemScale(id, responseText);
  790.  
  791.     if (!pv.remScale) {
  792.       pv.remScale = parseFloat(getComputedStyle(pv.body).fontSize) /
  793.                     parseFloat(getComputedStyle(document.documentElement).fontSize);
  794.       if (pv.remScale !== 1)
  795.         for (const id of pv.styles.keys())
  796.           Styles.applyRemScale(id);
  797.     }
  798.   }
  799.  
  800.   static async loadComments() {
  801.     const list = $(`#${pv.post.comments.id} .comments-list`);
  802.     const url = new URL(pv.finalUrl).origin +
  803.                 '/posts/' + pv.post.comments.id.match(/\d+/)[0] + '/comments';
  804.     list.innerHTML = (await Urler.get(url)).responseText;
  805.     $.remove('.hover-only-label', list);
  806.  
  807.     const oldIds = new Set([...list.children].map(e => e.id));
  808.     for (const cmt of list.children) {
  809.       if (!oldIds.has(cmt.id))
  810.         cmt.classList.add('new-comment-highlight');
  811.     }
  812.  
  813.     $.setStyle(list.closest('.comments'), ['display', 'block']);
  814.     Render.previewableLinks(list);
  815.     Render.hoverableUsers(list);
  816.   }
  817. }
  818.  
  819.  
  820. class Render {
  821.  
  822.   static all() {
  823.     pv.frame.classList.toggle(`${ID}-hasAnswerShelf`, pv.post.numAnswers > 0);
  824.     pv.frame.setAttribute(`${ID}-type`, pv.post.type);
  825.     pv.body.setAttribute(`${ID}-type`, pv.post.type);
  826.  
  827.     $.create(`a#${ID}-title.SEpreviewable`, {
  828.       href: pv.finalUrlOfQuestion,
  829.       textContent: pv.post.title,
  830.       parent: pv.body,
  831.     });
  832.  
  833.     $.create(`#${ID}-close`, {
  834.       title: 'Or press Esc key while the preview is focused (also when just shown)',
  835.       parent: pv.body,
  836.     });
  837.  
  838.     $.create(`#${ID}-meta`, {
  839.       parent: pv.body,
  840.       onmousedown: Sizer.onMouseDown,
  841.       children: [
  842.         Render._votes(),
  843.         pv.post.isQuestion
  844.           ? Render._questionMeta()
  845.           : Render._answerMeta(),
  846.       ],
  847.     });
  848.  
  849.     Render.previewableLinks(pv.post.doc);
  850.  
  851.     pv.post.answerShelf = pv.post.answers.map(Render._answer);
  852.     if (Security.noImages)
  853.       Security.embedImages(...pv.post.renderParts);
  854.  
  855.     pv.parts = $.create(`#${ID}-parts`, {
  856.       className: pv.post.isDeleted ? 'deleted-answer' : '',
  857.       tabIndex: 0,
  858.       scrollTop: 0,
  859.       parent: pv.body,
  860.       children: pv.post.renderParts,
  861.     });
  862.  
  863.     Render.hoverableUsers(pv.parts);
  864.  
  865.     if (pv.post.numAnswers) {
  866.       $.create(`#${ID}-answers`, {parent: pv.body}, [
  867.         pv.answersTitle,
  868.         pv.post.answerShelf,
  869.       ]);
  870.     } else {
  871.       $.remove(`#${ID}-answers`, pv.body);
  872.     }
  873.  
  874.     const ACTIONS_SEL = '.js-post-menu > div';
  875.     const elActions = $(ACTIONS_SEL);
  876.  
  877.     // delinkify/remove non-functional items in post-menu
  878.     $.remove('.js-share-link, .flag-post-link', pv.body);
  879.     for (const el of $.all(`${ACTIONS_SEL} button`)) {
  880.       const elWrapper = el.closest(`${ACTIONS_SEL} > div`);
  881.       if (elWrapper) elWrapper.remove();
  882.     }
  883.  
  884.     // add a timeline link
  885.     $.appendChildren(elActions, [
  886.       $.create('div.' + elActions.firstElementChild.className, [
  887.         $.create('a', {href: `/posts/${pv.post.id}/timeline`}, 'Timeline'),
  888.       ]),
  889.     ]);
  890.  
  891.     // prettify code blocks
  892.     hljs.configure({
  893.       languages: [
  894.         ...$.all('.post-taglist .post-tag', pv.post.doc).map($.text),
  895.         'javascript',
  896.         'html',
  897.       ],
  898.     });
  899.     $.all('pre > code').forEach(el => {
  900.       el = el.parentElement;
  901.       el.className = el.className.replace(/((?:^|\s)lang-)bsh(?=\s|$)/, '$1powershell');
  902.       hljs.highlightBlock(el);
  903.     });
  904.  
  905.     const leftovers = $.all('style, link, script');
  906.     for (const el of leftovers) {
  907.       if (el.classList.contains(Styles.REUSABLE))
  908.         el.classList.remove(Styles.REUSABLE);
  909.       else
  910.         el.remove();
  911.     }
  912.  
  913.     pv.post.html = null;
  914.     pv.post.core = null;
  915.     pv.post.renderParts = null;
  916.     pv.post.answers = null;
  917.     pv.post.answerShelf = null;
  918.   }
  919.  
  920.   /** @param {Element} container */
  921.   static previewableLinks(container) {
  922.     for (const a of $.all('a:not(.SEpreviewable)', container)) {
  923.       let href = a.getAttribute('href');
  924.       if (!href)
  925.         continue;
  926.       if (!href.includes('://')) {
  927.         href = a.href;
  928.         a.setAttribute('href', href);
  929.       }
  930.       if (Detector.rxPreviewablePost.test(href)) {
  931.         a.removeAttribute('title');
  932.         a.classList.add('SEpreviewable');
  933.       }
  934.     }
  935.   }
  936.  
  937.   /** @param {Element} container */
  938.   static hoverableUsers(container) {
  939.     for (const a of $.all('a[href*="/users/"]', container)) {
  940.       if (Detector.rxPreviewableSite.test(a.href) &&
  941.           a.pathname.match(/^\/users\/\d+/)) {
  942.         a.onmouseover = UserCard.onUserLinkHovered;
  943.         a.classList.add(`${ID}-userLink`);
  944.       }
  945.     }
  946.   }
  947.  
  948.   /** @param {Element} el */
  949.   static _answer(el) {
  950.     const shortUrl = $('.js-share-link', el).href.replace(/(\d+)\/\d+/, '$1');
  951.     const extraClasses =
  952.       (el.matches(pv.post.selector) ? ' SEpreviewed' : '') +
  953.       (el.matches('.deleted-answer') ? ' deleted-answer' : '') +
  954.       (el.matches('.accepted-answer') ? ` ${ID}-accepted` : '');
  955.     const author = $('.post-signature:last-child', el);
  956.     const title =
  957.       $.text('.user-details a', author) +
  958.       ' (rep ' +
  959.       $.text('.reputation-score', author) +
  960.       ')\n' +
  961.       $.text('.user-action-time', author);
  962.     let gravatar = $('img, .anonymous-gravatar, .community-wiki', author);
  963.     if (gravatar && Security.noImages)
  964.       Security.embedImages(gravatar);
  965.     if (gravatar && gravatar.src)
  966.       gravatar = $.create('img', {src: gravatar.src});
  967.     const a = $.create('a', {
  968.       href: shortUrl,
  969.       title: title,
  970.       className: 'SEpreviewable' + extraClasses,
  971.       textContent: $.text('.js-vote-count', el).replace(/^0$/, '\xA0') + ' ',
  972.       children: gravatar,
  973.     });
  974.     return [a, ' '];
  975.   }
  976.  
  977.   static _votes() {
  978.     const votes = $.text('.js-vote-count', pv.post.core.closest('.post-layout'));
  979.     if (Number(votes))
  980.       return $.create('b', `${votes} vote${Math.abs(votes) >= 2 ? 's' : ''}`);
  981.   }
  982.   static _questionMeta() {
  983.     try {
  984.       return [...$('time', pv.post.doc).closest('.grid').children]
  985.         .map(el => el.textContent.trim())
  986.         .map((s, i) => (i ? s.toLowerCase() : s))
  987.         .join(', ');
  988.     } catch (e) {
  989.       return '';
  990.     }
  991.   }
  992.  
  993.   static _answerMeta() {
  994.     return $.all('.user-action-time', pv.post.core.closest('.answer'))
  995.       .reverse()
  996.       .map($.text)
  997.       .join(', ');
  998.   }
  999. }
  1000.  
  1001.  
  1002. class UserCard {
  1003.  
  1004.   _fadeIn() {
  1005.     this._retakeId(this);
  1006.     $.setStyle(this.element,
  1007.       ['opacity', '0'],
  1008.       ['display', 'block']);
  1009.     this.timer = setTimeout(() => {
  1010.       if (this.timer)
  1011.         $.setStyle(this.element, ['opacity', '1']);
  1012.     });
  1013.   }
  1014.  
  1015.   _retakeId() {
  1016.     if (this.element.id !== 'user-menu') {
  1017.       const oldCard = $('#user-menu');
  1018.       if (oldCard)
  1019.         oldCard.id = oldCard.style.display = '';
  1020.       this.element.id = 'user-menu';
  1021.     }
  1022.   }
  1023.  
  1024.   // 'this' is the hoverable link enclosing the user's name/avatar
  1025.   static onUserLinkHovered() {
  1026.     clearTimeout(this[EXPANDO]);
  1027.     this[EXPANDO] = setTimeout(UserCard._show, PREVIEW_DELAY * 2, this);
  1028.   }
  1029.  
  1030.   /** @param {HTMLAnchorElement} a */
  1031.   static async _show(a) {
  1032.     if (!a.matches(':hover'))
  1033.       return;
  1034.     const el = a.nextElementSibling;
  1035.     const card = el && el.matches(`.${ID}-userCard`) && el[EXPANDO] ||
  1036.                  await UserCard._create(a);
  1037.     card._fadeIn();
  1038.   }
  1039.  
  1040.   /** @param {HTMLAnchorElement} a */
  1041.   static async _create(a) {
  1042.     const url = a.origin + '/users/user-info/' + Urler.getFirstNumber(a);
  1043.     let {html} = Cache.read(url) || {};
  1044.     if (!html) {
  1045.       html = (await Urler.get(url)).responseText;
  1046.       Cache.write({url, html, cacheDuration: CACHE_DURATION * 100});
  1047.     }
  1048.  
  1049.     const dom = Util.parseHtml(html);
  1050.     if (Security.noImages)
  1051.       Security.embedImages(dom);
  1052.  
  1053.     const b = a.getBoundingClientRect();
  1054.     const pb = pv.parts.getBoundingClientRect();
  1055.     const left = Math.min(b.left - 20, pb.right - 350) - pb.left + 'px';
  1056.     const isClipped = b.bottom + 100 > pb.bottom;
  1057.  
  1058.     const el = $.create(`#user-menu-tmp.${ID}-userCard`, {
  1059.       attributes: {
  1060.         style: `left: ${left} !important;` +
  1061.                (isClipped ? 'margin-top: -5rem !important;' : ''),
  1062.       },
  1063.       onmouseout: UserCard._onMouseOut,
  1064.       children: dom.body.children,
  1065.       after: a,
  1066.     });
  1067.  
  1068.     const card = new UserCard(el);
  1069.     Object.defineProperty(el, EXPANDO, {value: card});
  1070.     card.element = el;
  1071.     return card;
  1072.   }
  1073.  
  1074.   /** @param {MouseEvent} e */
  1075.   static _onMouseOut(e) {
  1076.     if (this.matches(':hover') ||
  1077.         this.style.opacity === '0' /* fading out already */)
  1078.       return;
  1079.  
  1080.     const self = /** @type {UserCard} */ this[EXPANDO];
  1081.     clearTimeout(self.timer);
  1082.     self.timer = 0;
  1083.  
  1084.     Util.fadeOut(this);
  1085.   }
  1086. }
  1087.  
  1088.  
  1089. class Sizer {
  1090.  
  1091.   static init() {
  1092.     Preview.setHeight(GM_getValue('height', innerHeight / 3) >> 0);
  1093.   }
  1094.  
  1095.   /** @param {MouseEvent} e */
  1096.   static onMouseDown(e) {
  1097.     if (e.button !== 0 || Util.hasKeyModifiers(e))
  1098.       return;
  1099.     Sizer._heightDelta = innerHeight - e.clientY - pv.frame.clientHeight;
  1100.     $.on('mousemove', document, Sizer._onMouseMove);
  1101.     $.on('mouseup', document, Sizer._onMouseUp);
  1102.   }
  1103.  
  1104.   /** @param {MouseEvent} e */
  1105.   static _onMouseMove(e) {
  1106.     Preview.setHeight(innerHeight - e.clientY - Sizer._heightDelta);
  1107.     getSelection().removeAllRanges();
  1108.   }
  1109.  
  1110.   /** @param {MouseEvent} e */
  1111.   static _onMouseUp(e) {
  1112.     GM_setValue('height', pv.frame.clientHeight);
  1113.     $.off('mouseup', document, Sizer._onMouseUp);
  1114.     $.off('mousemove', document, Sizer._onMouseMove);
  1115.   }
  1116. }
  1117.  
  1118.  
  1119. class ScrollLock {
  1120.  
  1121.   static enable() {
  1122.     if (ScrollLock.active)
  1123.       return;
  1124.     ScrollLock.active = true;
  1125.     ScrollLock.x = scrollX;
  1126.     ScrollLock.y = scrollY;
  1127.     $.on('mouseover', document.body, ScrollLock._onMouseOver);
  1128.     $.on('scroll', document, ScrollLock._onScroll);
  1129.   }
  1130.  
  1131.   static disable() {
  1132.     ScrollLock.active = false;
  1133.     $.off('mouseover', document.body, ScrollLock._onMouseOver);
  1134.     $.off('scroll', document, ScrollLock._onScroll);
  1135.   }
  1136.  
  1137.   static _onMouseOver() {
  1138.     if (ScrollLock.active)
  1139.       ScrollLock.disable();
  1140.   }
  1141.  
  1142.   static _onScroll() {
  1143.     scrollTo(ScrollLock.x, ScrollLock.y);
  1144.   }
  1145. }
  1146.  
  1147.  
  1148. class Security {
  1149.  
  1150.   static init() {
  1151.     if (Detector.isStackExchangePage) {
  1152.       Security.checked = true;
  1153.       Security.check = null;
  1154.     }
  1155.     Security.init = true;
  1156.   }
  1157.  
  1158.   static async check() {
  1159.     Security.noImages = false;
  1160.     Security._resolveOnReady = [];
  1161.     Security._imageCache = new Map();
  1162.  
  1163.     const {headers} = await fetch(location.href, {
  1164.       method: 'HEAD',
  1165.       cache: 'force-cache',
  1166.       mode: 'same-origin',
  1167.       credentials: 'same-origin',
  1168.     });
  1169.     const csp = headers.get('Content-Security-Policy');
  1170.     const imgSrc = /(?:^|[\s;])img-src\s+([^;]+)/i.test(csp) && RegExp.$1.trim();
  1171.     if (imgSrc)
  1172.       Security.noImages = !/(^\s)(\*|https?:)(\s|$)/.test(imgSrc);
  1173.  
  1174.     Security._resolveOnReady.forEach(fn => fn());
  1175.     Security._resolveOnReady = null;
  1176.     Security.checked = true;
  1177.     Security.check = null;
  1178.   }
  1179.  
  1180.   /** @return Promise<void> */
  1181.   static ready() {
  1182.     return Security.checked ?
  1183.       Promise.resolve() :
  1184.       new Promise(done => Security._resolveOnReady.push(done));
  1185.   }
  1186.  
  1187.   static embedImages(...containers) {
  1188.     for (const container of containers) {
  1189.       if (!container)
  1190.         continue;
  1191.       if (Util.isIterable(container)) {
  1192.         Security.embedImages(...container);
  1193.         continue;
  1194.       }
  1195.       if (container.localName === 'img') {
  1196.         Security._embedImage(container);
  1197.         continue;
  1198.       }
  1199.       for (const img of container.getElementsByTagName('img'))
  1200.         Security._embedImage(img);
  1201.     }
  1202.   }
  1203.  
  1204.   static _embedImage(img) {
  1205.     const src = img.src;
  1206.     if (!src || src.startsWith('data:'))
  1207.       return;
  1208.     const data = Security._imageCache.get(src);
  1209.     const alreadyFetching = Array.isArray(data);
  1210.     if (alreadyFetching) {
  1211.       data.push(img);
  1212.     } else if (data) {
  1213.       img.src = data;
  1214.       return;
  1215.     } else {
  1216.       Security._imageCache.set(src, [img]);
  1217.       Security._fetchImage(src);
  1218.     }
  1219.     $.setStyle(img, ['visibility', 'hidden']);
  1220.     img.dataset.src = src;
  1221.     img.removeAttribute('src');
  1222.   }
  1223.  
  1224.   static async _fetchImage(src) {
  1225.     const r = await Urler.get({url: src, responseType: 'blob'});
  1226.     const type = Util.getResponseMimeType(r.responseHeaders);
  1227.     const blob = r.response;
  1228.     const blobType = blob.type;
  1229.     let dataUri = await Util.blobToBase64(blob);
  1230.     if (blobType !== type)
  1231.       dataUri = 'data:' + type + dataUri.slice(dataUri.indexOf(';'));
  1232.  
  1233.     const images = Security._imageCache.get(src);
  1234.     Security._imageCache.set(src, dataUri);
  1235.  
  1236.     let detached = false;
  1237.     for (const el of images) {
  1238.       el.src = dataUri;
  1239.       el.style.removeProperty('visibility');
  1240.       if (!detached && el.ownerDocument !== document)
  1241.         detached = true;
  1242.     }
  1243.  
  1244.     if (detached) {
  1245.       for (const el of $.all(`img[data-src="${src}"]`)) {
  1246.         el.src = dataUri;
  1247.         el.style.removeProperty('visibility');
  1248.       }
  1249.     }
  1250.   }
  1251. }
  1252.  
  1253.  
  1254. // eslint-disable-next-line no-redeclare
  1255. class Cache {
  1256.  
  1257.   static init() {
  1258.     Cache.timers = new Map();
  1259.     setTimeout(Cache._cleanup, 10e3);
  1260.   }
  1261.  
  1262.   static read(url) {
  1263.     const keyUrl = Urler.makeCacheable(url);
  1264.     const [time, expires, finalUrl = url] = (localStorage[keyUrl] || '').split('\t');
  1265.     const keyFinalUrl = Urler.makeCacheable(finalUrl);
  1266.     return expires > Date.now() && {
  1267.       time,
  1268.       finalUrl,
  1269.       html: LZStringUnsafe.decompressFromUTF16(localStorage[keyFinalUrl + '\thtml']),
  1270.     };
  1271.   }
  1272.  
  1273.   // standard keyUrl = time,expiry
  1274.   //          keyUrl\thtml = html
  1275.   // redirected keyUrl = time,expiry,finalUrl
  1276.   //            keyFinalUrl = time,expiry
  1277.   //            keyFinalUrl\thtml = html
  1278.   static write({url, finalUrl, html, cacheDuration = CACHE_DURATION}) {
  1279.  
  1280.     cacheDuration = Math.max(CACHE_DURATION, Math.min(0x7FFF0000, cacheDuration >> 0));
  1281.     finalUrl = (finalUrl || url).replace(/[?#].*/, '');
  1282.  
  1283.     const keyUrl = Urler.makeCacheable(url);
  1284.     const keyFinalUrl = Urler.makeCacheable(finalUrl);
  1285.     const lz = LZStringUnsafe.compressToUTF16(html);
  1286.  
  1287.     if (!Util.tryCatch(Cache._writeRaw, keyFinalUrl + '\thtml', lz)) {
  1288.       Cache._cleanup({aggressive: true});
  1289.       if (!Util.tryCatch(Cache._writeRaw, keyFinalUrl + '\thtml', lz))
  1290.         return Util.error('localStorage write error');
  1291.     }
  1292.  
  1293.     const time = Date.now();
  1294.     const expiry = time + cacheDuration;
  1295.     localStorage[keyFinalUrl] = time + '\t' + expiry;
  1296.     if (keyUrl !== keyFinalUrl)
  1297.       localStorage[keyUrl] = time + '\t' + expiry + '\t' + finalUrl;
  1298.  
  1299.     const t = setTimeout(Cache._delete, cacheDuration + 1000,
  1300.       keyUrl,
  1301.       keyFinalUrl,
  1302.       keyFinalUrl + '\thtml');
  1303.  
  1304.     for (const url of [keyUrl, keyFinalUrl]) {
  1305.       clearTimeout(Cache.timers.get(url));
  1306.       Cache.timers.set(url, t);
  1307.     }
  1308.   }
  1309.  
  1310.   static _writeRaw(k, v) {
  1311.     localStorage[k] = v;
  1312.     return true;
  1313.   }
  1314.  
  1315.   static _delete(...keys) {
  1316.     for (const k of keys) {
  1317.       delete localStorage[k];
  1318.       Cache.timers.delete(k);
  1319.     }
  1320.   }
  1321.  
  1322.   static _cleanup({aggressive = false} = {}) {
  1323.     for (const k in localStorage) {
  1324.       if ((k.startsWith('http://') || k.startsWith('https://')) &&
  1325.           !k.includes('\t')) {
  1326.         const [, expires, url] = (localStorage[k] || '').split('\t');
  1327.         if (Number(expires) > Date.now() && !aggressive)
  1328.           break;
  1329.         if (url) {
  1330.           delete localStorage[url];
  1331.           Cache.timers.delete(url);
  1332.         }
  1333.         delete localStorage[(url || k) + '\thtml'];
  1334.         delete localStorage[k];
  1335.         Cache.timers.delete(k);
  1336.       }
  1337.     }
  1338.   }
  1339. }
  1340.  
  1341.  
  1342. class Urler {
  1343.  
  1344.   static init() {
  1345.     Urler.xhr = null;
  1346.     Urler.xhrNoSSL = new Set();
  1347.     Urler.init = true;
  1348.   }
  1349.  
  1350.   static getFirstNumber(url) {
  1351.     if (typeof url === 'string')
  1352.       url = new URL(url);
  1353.     return url.pathname.match(/\/(\d+)/)[1];
  1354.   }
  1355.  
  1356.   static makeHttps(url) {
  1357.     if (!url)
  1358.       return '';
  1359.     if (url.startsWith('http:'))
  1360.       return 'https:' + url.slice(5);
  1361.     return url;
  1362.   }
  1363.  
  1364.   // strips queries and hashes and anything after the main part
  1365.   // https://site/questions/NNNNNN/title/
  1366.   static makeCacheable(url) {
  1367.     return url
  1368.       .replace(/(\/q(?:uestions)?\/\d+\/[^/]+).*/, '$1')
  1369.       .replace(/(\/a(?:nswers)?\/\d+).*/, '$1')
  1370.       .replace(/[?#].*$/, '');
  1371.   }
  1372.  
  1373.   static get(options) {
  1374.     if (!options.url)
  1375.       options = {url: options, method: 'GET'};
  1376.     if (!options.method)
  1377.       options = Object.assign({method: 'GET'}, options);
  1378.  
  1379.     let url = options.url;
  1380.     const hostname = new URL(url).hostname;
  1381.  
  1382.     if (Urler.xhrNoSSL.has(hostname)) {
  1383.       url = url.replace(/^https/, 'http');
  1384.     } else {
  1385.       url = Urler.makeHttps(url);
  1386.       const _onerror = options.onerror;
  1387.       options.onerror = () => {
  1388.         options.onerror = _onerror;
  1389.         options.url = url.replace(/^https/, 'http');
  1390.         Urler.xhrNoSSL.add(hostname);
  1391.         return Urler.get(options);
  1392.       };
  1393.     }
  1394.  
  1395.     return new Promise(resolve => {
  1396.       let xhr;
  1397.       options.onload = r => {
  1398.         if (pv.xhr === xhr)
  1399.           pv.xhr = null;
  1400.         resolve(r);
  1401.       };
  1402.       options.url = url;
  1403.       xhr = pv.xhr = GM_xmlhttpRequest(options);
  1404.     });
  1405.   }
  1406. }
  1407.  
  1408.  
  1409. class Util {
  1410.  
  1411.   static tryCatch(fn, ...args) {
  1412.     try {
  1413.       return fn(...args);
  1414.     } catch (e) {}
  1415.   }
  1416.  
  1417.   static isIterable(o) {
  1418.     return typeof o === 'object' && Symbol.iterator in o;
  1419.   }
  1420.  
  1421.   static parseHtml(html) {
  1422.     if (!Util.parser)
  1423.       Util.parser = new DOMParser();
  1424.     return Util.parser.parseFromString(html, 'text/html');
  1425.   }
  1426.  
  1427.   static extractTime(element) {
  1428.     return new Date(element.title).getTime();
  1429.   }
  1430.  
  1431.   static getResponseMimeType(headers) {
  1432.     return headers.match(/^\s*content-type:\s*(.*)|$/mi)[1] ||
  1433.            'image/png';
  1434.   }
  1435.  
  1436.   static getResponseDate(headers) {
  1437.     try {
  1438.       return new Date(headers.match(/^\s*date:\s*(.*)/mi)[1]);
  1439.     } catch (e) {}
  1440.   }
  1441.  
  1442.   static blobToBase64(blob) {
  1443.     return new Promise((resolve, reject) => {
  1444.       const reader = new FileReader();
  1445.       reader.onerror = reject;
  1446.       reader.onload = e => resolve(e.target.result);
  1447.       reader.readAsDataURL(blob);
  1448.     });
  1449.   }
  1450.  
  1451.   static async sha256(str) {
  1452.     if (!pv.utf8encoder)
  1453.       pv.utf8encoder = new TextEncoder('utf-8');
  1454.     const buf = await crypto.subtle.digest('SHA-256', pv.utf8encoder.encode(str));
  1455.     const blob = new Blob([buf]);
  1456.     const url = await Util.blobToBase64(blob);
  1457.     return url.slice(url.indexOf(',') + 1);
  1458.   }
  1459.  
  1460.   /** @param {KeyboardEvent} e */
  1461.   static hasKeyModifiers(e) {
  1462.     return e.ctrlKey || e.altKey || e.shiftKey || e.metaKey;
  1463.   }
  1464.  
  1465.   static fadeOut(el, transition) {
  1466.     return new Promise(resolve => {
  1467.       if (transition) {
  1468.         if (typeof transition === 'number')
  1469.           transition = `opacity ${transition}s ease-in-out`;
  1470.         $.setStyle(el, ['transition', transition]);
  1471.         setTimeout(doFadeOut);
  1472.       } else {
  1473.         doFadeOut();
  1474.       }
  1475.       function doFadeOut() {
  1476.         $.setStyle(el, ['opacity', '0']);
  1477.         $.on('transitionend', el, done);
  1478.         $.on('visibilitychange', el, done);
  1479.       }
  1480.       function done() {
  1481.         $.off('transitionend', el, done);
  1482.         $.off('visibilitychange', el, done);
  1483.         if (el.style.opacity === '0')
  1484.           $.setStyle(el, ['display', 'none']);
  1485.         resolve();
  1486.       }
  1487.     });
  1488.   }
  1489.  
  1490.   /** @param {KeyboardEvent} e */
  1491.   static consumeEsc(e) {
  1492.     if (e.key === 'Escape')
  1493.       e.preventDefault();
  1494.   }
  1495.  
  1496.   static error(...args) {
  1497.     console.error(GM_info.script.name, ...args);
  1498.   }
  1499. }
  1500.  
  1501.  
  1502. class Styles {
  1503.  
  1504.   static init(isDark) {
  1505.     if (Styles.isDark === isDark)
  1506.       return;
  1507.  
  1508.     Styles.isDark = isDark;
  1509.     Styles.REUSABLE = `${ID}-reusable`;
  1510.  
  1511.     const KBD_COLOR = '#0008';
  1512.  
  1513.     // language=HTML
  1514.     const SVG_ARROW = btoa(`
  1515.       <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 16 16">
  1516.         <path stroke="${KBD_COLOR}" stroke-width="3" fill="none"
  1517.               d="M2.5,8.5H15 M9,2L2.5,8.5L9,15"/>
  1518.       </svg>`
  1519.       .replace(/>\s+</g, '><')
  1520.       .replace(/[\r\n]/g, ' ')
  1521.       .replace(/\s\s+/g, ' ')
  1522.       .trim()
  1523.     );
  1524.  
  1525.     const IMPORTANT = '!important;';
  1526.  
  1527.     // language=CSS
  1528.     pv.stylesOverride = [
  1529.       `
  1530.       :host {
  1531.         all: initial;
  1532.         border-color: transparent;
  1533.         display: none;
  1534.         opacity: 0;
  1535.         height: 33%;
  1536.         transition: opacity .25s cubic-bezier(.88,.02,.92,.66),
  1537.                     border-color .25s ease-in-out;
  1538.       }
  1539.       `,
  1540.  
  1541.       `
  1542.       :host {
  1543.         box-sizing: content-box;
  1544.         width: ${WIDTH}px;
  1545.         min-height: ${MIN_HEIGHT}px;
  1546.         position: fixed;
  1547.         right: 0;
  1548.         bottom: 0;
  1549.         padding: 0;
  1550.         margin: 0;
  1551.         background: white;
  1552.         box-shadow: 0 0 100px rgba(0,0,0,0.5);
  1553.         z-index: 999999;
  1554.         border-width: ${TOP_BORDER}px ${BORDER}px ${BORDER}px;
  1555.         border-style: solid;
  1556.       }
  1557.       :host(:not([style*="opacity: 1"])) {
  1558.         pointer-events: none;
  1559.       }
  1560.       :host([\\type$="question"].\\hasAnswerShelf) {
  1561.         border-image: linear-gradient(
  1562.           ${colors.question.back} 66%,
  1563.           ${colors.answer.back}) 1 1;
  1564.       }
  1565.       `.replace(/;/g, IMPORTANT),
  1566.  
  1567.       ...Object.entries(colors).map(([type, colors]) => `
  1568.         :host([\\type$="${type}"]) {
  1569.           border-color: ${colors.back} !important;
  1570.         }
  1571.       `),
  1572.  
  1573.       `
  1574.       #\\body {
  1575.         min-width: unset!important;
  1576.         box-shadow: none!important;
  1577.         padding: 0!important;
  1578.         margin: 0!important;
  1579.         background: ${colors.body.back}!important;
  1580.         color: ${colors.body.fore}!important;
  1581.         display: flex;
  1582.         flex-direction: column;
  1583.         height: 100%;
  1584.       }
  1585.  
  1586.       #\\title {
  1587.         all: unset;
  1588.         display: block;
  1589.         padding: 12px ${PADDING}px;
  1590.         font-weight: bold;
  1591.         font-size: 18px;
  1592.         line-height: 1.2;
  1593.         cursor: pointer;
  1594.       }
  1595.       #\\title:hover {
  1596.         text-decoration: underline;
  1597.         text-decoration-skip: ink;
  1598.       }
  1599.       #\\title:hover + #\\meta {
  1600.         opacity: 1.0;
  1601.       }
  1602.  
  1603.       #\\meta {
  1604.         position: absolute;
  1605.         font: bold 14px/${TOP_BORDER}px sans-serif;
  1606.         height: ${TOP_BORDER}px;
  1607.         top: -${TOP_BORDER}px;
  1608.         left: -${BORDER}px;
  1609.         right: ${BORDER * 2}px;
  1610.         padding: 0 0 0 ${BORDER + PADDING}px;
  1611.         display: flex;
  1612.         align-items: center;
  1613.         cursor: s-resize;
  1614.       }
  1615.       #\\meta b {
  1616.         height: ${TOP_BORDER}px;
  1617.         display: inline-block;
  1618.         padding: 0 6px;
  1619.         margin-left: -6px;
  1620.         margin-right: 3px;
  1621.       }
  1622.  
  1623.       #\\close {
  1624.         position: absolute;
  1625.         top: -${TOP_BORDER}px;
  1626.         right: -${BORDER}px;
  1627.         width: ${BORDER * 3}px;
  1628.         flex: none;
  1629.         cursor: pointer;
  1630.         padding: .5ex 1ex;
  1631.         font: normal 15px/1.0 sans-serif;
  1632.         color: #fff8;
  1633.       }
  1634.       #\\close:after {
  1635.         content: "x";
  1636.       }
  1637.       #\\close:active {
  1638.         background-color: rgba(0,0,0,.2);
  1639.       }
  1640.       #\\close:hover {
  1641.         background-color: rgba(0,0,0,.1);
  1642.       }
  1643.  
  1644.       #\\parts {
  1645.         position: relative;
  1646.         overflow-y: overlay; /* will replace with scrollbar-gutter once it's implemented */
  1647.         overflow-x: hidden;
  1648.         flex-grow: 2;
  1649.         outline: none;
  1650.         margin: 0;
  1651.         padding: ${PADDING}px ${PADDING - PROSE_MARGIN}px ${PADDING}px ${PADDING}px !important;
  1652.       }
  1653.       #\\parts > .question-status {
  1654.         margin: -${PADDING}px -${PADDING}px ${PADDING}px;
  1655.         padding-left: ${PADDING}px;
  1656.       }
  1657.       #\\parts .question-originals-of-duplicate {
  1658.         margin: -${PADDING}px -${PADDING}px ${PADDING}px;
  1659.         padding: ${PADDING / 2 >> 0}px ${PADDING}px;
  1660.       }
  1661.       #\\parts > .question-status h2 {
  1662.         font-weight: normal;
  1663.       }
  1664.       #\\parts a.SEpreviewable {
  1665.         text-decoration: underline !important;
  1666.         text-decoration-skip: ink;
  1667.       }
  1668.  
  1669.       #\\parts .comment-actions {
  1670.         width: 20px !important;
  1671.       }
  1672.       #\\parts .comment-edit,
  1673.       #\\parts .delete-tag,
  1674.       #\\parts .comment-actions > :not(.comment-score) {
  1675.         display: none;
  1676.       }
  1677.       #\\parts .comments {
  1678.         border-top: none;
  1679.       }
  1680.       #\\parts .comments .comment:last-child .comment-text {
  1681.         border-bottom: none;
  1682.       }
  1683.       #\\parts .comments .new-comment-highlight .comment-text {
  1684.         -webkit-animation: highlight 9s cubic-bezier(0,.8,.37,.88);
  1685.         -moz-animation: highlight 9s cubic-bezier(0,.8,.37,.88);
  1686.         animation: highlight 9s cubic-bezier(0,.8,.37,.88);
  1687.       }
  1688.       #\\parts .post-menu > span {
  1689.         opacity: .35;
  1690.       }
  1691.  
  1692.       #\\parts #user-menu {
  1693.         position: absolute;
  1694.       }
  1695.       .\\userCard {
  1696.         position: absolute;
  1697.         display: none;
  1698.         transition: opacity .25s cubic-bezier(.88,.02,.92,.66) .5s;
  1699.         margin-top: -3rem;
  1700.       }
  1701.       #\\parts .wmd-preview a:not(.post-tag),
  1702.       #\\parts .postcell a:not(.post-tag),
  1703.       #\\parts .comment-copy a:not(.post-tag) {
  1704.         border-bottom: none;
  1705.       }
  1706.  
  1707.       #\\answers-title {
  1708.         margin: .5ex 1ex 0 0;
  1709.         font-size: 18px;
  1710.         line-height: 1.0;
  1711.         float: left;
  1712.       }
  1713.       #\\answers-title p {
  1714.         font-size: 11px;
  1715.         font-weight: normal;
  1716.         max-width: 8em;
  1717.         line-height: 1.0;
  1718.         margin: 1ex 0 0 0;
  1719.         padding: 0;
  1720.       }
  1721.       #\\answers-title b,
  1722.       #\\answers-title label {
  1723.         background: linear-gradient(#fff8 30%, #fff);
  1724.         width: 10px;
  1725.         height: 10px;
  1726.         padding: 2px;
  1727.         margin-right: 2px;
  1728.         box-shadow: 0 1px 3px #0008;
  1729.         border-radius: 3px;
  1730.         font-weight: normal;
  1731.         display: inline-block;
  1732.         vertical-align: middle;
  1733.       }
  1734.       #\\answers-title b::after {
  1735.         content: "";
  1736.         display: block;
  1737.         width: 100%;
  1738.         height: 100%;
  1739.         background: url('data:image/svg+xml;base64,${SVG_ARROW}') no-repeat center;
  1740.       }
  1741.       #\\answers-title b[mirrored]::after {
  1742.         transform: scaleX(-1);
  1743.       }
  1744.       #\\answers-title label {
  1745.         width: auto;
  1746.         color: ${KBD_COLOR};
  1747.       }
  1748.  
  1749.       #\\answers {
  1750.         all: unset;
  1751.         display: block;
  1752.         padding: 10px 10px 10px ${PADDING}px;
  1753.         font-weight: bold;
  1754.         line-height: 1.0;
  1755.         border-top: 4px solid ${colors.answer.back}5e;
  1756.         background-color: ${colors.answer.back}5e;
  1757.         color: ${colors.answer.fore};
  1758.         word-break: break-word;
  1759.       }
  1760.       #\\answers a {
  1761.         color: ${colors.answer.fore};
  1762.         text-decoration: none;
  1763.         font-size: 11px;
  1764.         font-family: monospace;
  1765.         width: 32px !important;
  1766.         display: inline-block;
  1767.         position: relative;
  1768.         vertical-align: top;
  1769.         margin: 0 1ex 1ex 0;
  1770.         padding: 0 0 1.1ex 0;
  1771.       }
  1772.       [\\type*="deleted"] #\\answers a {
  1773.         color: ${colors.deleted.fore};
  1774.       }
  1775.       #\\answers img {
  1776.         width: 32px;
  1777.         height: 32px;
  1778.       }
  1779.       #\\answers a.deleted-answer {
  1780.         color: ${colors.deleted.fore};
  1781.         background: transparent;
  1782.         opacity: 0.25;
  1783.       }
  1784.       #\\answers a.deleted-answer:hover {
  1785.         opacity: 1.0;
  1786.       }
  1787.       #\\answers a:hover:not(.SEpreviewed) {
  1788.         text-decoration: underline;
  1789.         text-decoration-skip: ink;
  1790.       }
  1791.       #\\answers a.SEpreviewed {
  1792.         background-color: ${colors.answer.fore};
  1793.         color: ${colors.answer.foreInv};
  1794.         outline: 4px solid ${colors.answer.fore};
  1795.       }
  1796.       #\\answers a::after {
  1797.         white-space: nowrap;
  1798.         overflow: hidden;
  1799.         text-overflow: ellipsis;
  1800.         max-width: 40px;
  1801.         position: absolute;
  1802.         content: attr(title);
  1803.         top: 44px;
  1804.         left: 0;
  1805.         font: normal .75rem/1.0 sans-serif;
  1806.         opacity: .7;
  1807.       }
  1808.       #\\answers a:only-child::after {
  1809.         max-width: calc(${WIDTH}px - 10em);
  1810.       }
  1811.       #\\answers a:hover::after {
  1812.         opacity: 1;
  1813.       }
  1814.       .\\accepted::before {
  1815.         content: "✔";
  1816.         position: absolute;
  1817.         display: block;
  1818.         top: 1.3ex;
  1819.         right: -0.7ex;
  1820.         font-size: 32px;
  1821.         color: #4bff2c;
  1822.         text-shadow: 1px 2px 2px rgba(0,0,0,0.5);
  1823.       }
  1824.  
  1825.       @-webkit-keyframes highlight {
  1826.         from {background: #ffcf78}
  1827.         to   {background: none}
  1828.       }
  1829.       `,
  1830.  
  1831.       ...Object.keys(colors).map(s => `
  1832.         #\\title {
  1833.           background-color: ${colors[s].back}5e;
  1834.           color: ${colors[s].fore};
  1835.         }
  1836.         #\\meta {
  1837.           color: ${colors[s].fore};
  1838.         }
  1839.         #\\meta b {
  1840.           color: ${colors[s].foreInv};
  1841.           background: ${colors[s].fore};
  1842.         }
  1843.         #\\close {
  1844.           color: ${colors[s].fore};
  1845.         }
  1846.         #\\parts::-webkit-scrollbar {
  1847.           background-color: ${colors[s].back}19;
  1848.         }
  1849.         #\\parts::-webkit-scrollbar-thumb {
  1850.           background-color: ${colors[s].back}32;
  1851.         }
  1852.         #\\parts::-webkit-scrollbar-thumb:hover {
  1853.           background-color: ${colors[s].back}4b;
  1854.         }
  1855.         #\\parts::-webkit-scrollbar-thumb:active {
  1856.           background-color: ${colors[s].back}c0;
  1857.         }
  1858.       `
  1859.       // language=JS
  1860.         .replace(/#\\/g, `[\\type$="${s}"] $&`)
  1861.       ),
  1862.  
  1863.       ...['deleted', 'closed'].map(s => /* language=CSS */ `
  1864.         #\\answers {
  1865.           border-top-color: ${colors[s].back}5e;
  1866.           background-color: ${colors[s].back}5e;
  1867.           color: ${colors[s].fore};
  1868.         }
  1869.         #\\answers a.SEpreviewed {
  1870.           background-color: ${colors[s].fore};
  1871.           color: ${colors[s].foreInv};
  1872.         }
  1873.         #\\answers a.SEpreviewed:after {
  1874.           border-color: ${colors[s].fore};
  1875.         }
  1876.       `
  1877.       // language=JS
  1878.         .replace(/#\\/g, `[\\type$="${s}"] $&`)
  1879.       ),
  1880.  
  1881.       GM_getResourceText(`HL-style${isDark ? '-dark' : ''}`),
  1882.     ].join('\n').replace(/\\/g, `${ID}-`);
  1883.   }
  1884.  
  1885.   static applyRemScale(id, css) {
  1886.     const el = pv.styles.get(id);
  1887.     if (pv.remScale && pv.remScale !== 1 && !pv.stylesScaled.has(id)) {
  1888.       css = (css || el.textContent).replace(/([:\s])((?:\d*\.?)?\d+)(?=rem([;}\s]|\/\*))/gi,
  1889.         (_, prev, size) => prev + (pv.remScale * size));
  1890.       pv.stylesScaled.add(id);
  1891.     }
  1892.     el.textContent = css;
  1893.   }
  1894. }
  1895.  
  1896. function $(selector, node = pv.shadow) {
  1897.   return node && node.querySelector(selector);
  1898. }
  1899.  
  1900. Object.assign($, {
  1901.  
  1902.   all(selector, node = pv.shadow) {
  1903.     return node ? [...node.querySelectorAll(selector)] : [];
  1904.   },
  1905.  
  1906.   on(eventName, node, fn, options) {
  1907.     return node.addEventListener(eventName, fn, options);
  1908.   },
  1909.  
  1910.   off(eventName, node, fn, options) {
  1911.     return node.removeEventListener(eventName, fn, options);
  1912.   },
  1913.  
  1914.   remove(selector, node = pv.shadow) {
  1915.     for (const el of node.querySelectorAll(selector))
  1916.       el.remove();
  1917.   },
  1918.  
  1919.   text(selector, node = pv.shadow) {
  1920.     const el = typeof selector === 'string' ?
  1921.       node && node.querySelector(selector) :
  1922.       selector;
  1923.     return el ? el.textContent.trim() : '';
  1924.   },
  1925.  
  1926.   create(
  1927.     selector,
  1928.     opts = {},
  1929.     children = opts.children ||
  1930.                (typeof opts !== 'object' || Util.isIterable(opts)) && opts
  1931.   ) {
  1932.     const EOL = selector.length;
  1933.     const idStart = (selector.indexOf('#') + 1 || EOL + 1) - 1;
  1934.     const clsStart = (selector.indexOf('.', idStart < EOL ? idStart : 0) + 1 || EOL + 1) - 1;
  1935.     const tagEnd = Math.min(idStart, clsStart);
  1936.     const tag = (tagEnd < EOL ? selector.slice(0, tagEnd) : selector) || opts.tag || 'div';
  1937.     const id = idStart < EOL && selector.slice(idStart + 1, clsStart) || opts.id || '';
  1938.     const cls = clsStart < EOL && selector.slice(clsStart + 1).replace(/\./g, ' ') ||
  1939.                 opts.className ||
  1940.                 '';
  1941.     const el = id && pv.shadow && pv.shadow.getElementById(id) ||
  1942.                document.createElement(tag);
  1943.     if (el.id !== id)
  1944.       el.id = id;
  1945.     if (el.className !== cls)
  1946.       el.className = cls;
  1947.     const hasOwnProperty = Object.hasOwnProperty;
  1948.     for (const key in opts) {
  1949.       if (!hasOwnProperty.call(opts, key))
  1950.         continue;
  1951.       const value = opts[key];
  1952.       switch (key) {
  1953.         case 'tag':
  1954.         case 'id':
  1955.         case 'className':
  1956.         case 'children':
  1957.           break;
  1958.         case 'dataset': {
  1959.           const dataset = el.dataset;
  1960.           for (const k in value) {
  1961.             if (hasOwnProperty.call(value, k)) {
  1962.               const v = value[k];
  1963.               if (dataset[k] !== v)
  1964.                 dataset[k] = v;
  1965.             }
  1966.           }
  1967.           break;
  1968.         }
  1969.         case 'attributes': {
  1970.           for (const k in value) {
  1971.             if (hasOwnProperty.call(value, k)) {
  1972.               const v = value[k];
  1973.               if (el.getAttribute(k) !== v)
  1974.                 el.setAttribute(k, v);
  1975.             }
  1976.           }
  1977.           break;
  1978.         }
  1979.         default:
  1980.           if (el[key] !== value)
  1981.             el[key] = value;
  1982.       }
  1983.     }
  1984.     if (children) {
  1985.       if (!hasOwnProperty.call(opts, 'textContent'))
  1986.         el.textContent = '';
  1987.       $.appendChildren(el, children);
  1988.     }
  1989.     let before, after, parent;
  1990.     if ((before = opts.before) && before !== el.nextSibling && before !== el)
  1991.       before.insertAdjacentElement('beforebegin', el);
  1992.     else if ((after = opts.after) && after !== el.previousSibling && after !== el)
  1993.       after.insertAdjacentElement('afterend', el);
  1994.     else if ((parent = opts.parent) && parent !== el.parentNode)
  1995.       parent.appendChild(el);
  1996.     return el;
  1997.   },
  1998.  
  1999.   appendChild(parent, child, shouldClone = true) {
  2000.     if (!child)
  2001.       return;
  2002.     if (child.nodeType)
  2003.       return parent.appendChild(shouldClone ? document.importNode(child, true) : child);
  2004.     if (Util.isIterable(child))
  2005.       return $.appendChildren(parent, child, shouldClone);
  2006.     else
  2007.       return parent.appendChild(document.createTextNode(child));
  2008.   },
  2009.  
  2010.   appendChildren(newParent, children) {
  2011.     if (!Util.isIterable(children))
  2012.       return $.appendChild(newParent, children);
  2013.     const fragment = document.createDocumentFragment();
  2014.     for (const el of children)
  2015.       $.appendChild(fragment, el);
  2016.     return newParent.appendChild(fragment);
  2017.   },
  2018.  
  2019.   setStyle(el, ...props) {
  2020.     const style = el.style;
  2021.     const s0 = style.cssText;
  2022.     let s = s0;
  2023.  
  2024.     for (const p of props) {
  2025.       if (!p)
  2026.         continue;
  2027.  
  2028.       const [name, value, important = true] = p;
  2029.       const rValue = value + (important && value ? ' !important' : '');
  2030.       const rx = new RegExp(`(^|[\\s;])${name}(\\s*:\\s*)([^;]*?)(\\s*(?:;|$))`, 'i');
  2031.       const m = rx.exec(s);
  2032.  
  2033.       if (!m && value) {
  2034.         const rule = name + ': ' + rValue;
  2035.         s += !s || s.endsWith(';') ? rule : '; ' + rule;
  2036.         continue;
  2037.       }
  2038.  
  2039.       if (!m && !value)
  2040.         continue;
  2041.  
  2042.       const [, sep1, sep2, oldValue, sep3] = m;
  2043.       if (value !== oldValue) {
  2044.         s = s.slice(0, m.index) +
  2045.             sep1 + (rValue ? name + sep2 + rValue + sep3 : '') +
  2046.             s.slice(m.index + m[0].length);
  2047.       }
  2048.     }
  2049.  
  2050.     if (s !== s0)
  2051.       style.cssText = s;
  2052.   },
  2053. });