aboutsummaryrefslogtreecommitdiff
path: root/src/external/purify.min.js.map
blob: e4ff912ac7f7fb24c6b49bcefe14e1c319153ee5 (plain)
1
{"version":3,"file":"purify.min.js","sources":["../src/utils.js","../src/tags.js","../src/attrs.js","../src/regexp.js","../src/purify.js"],"sourcesContent":["const {\n  entries,\n  setPrototypeOf,\n  isFrozen,\n  getPrototypeOf,\n  getOwnPropertyDescriptor,\n} = Object;\n\nlet { freeze, seal, create } = Object; // eslint-disable-line import/no-mutable-exports\nlet { apply, construct } = typeof Reflect !== 'undefined' && Reflect;\n\nif (!apply) {\n  apply = function (fun, thisValue, args) {\n    return fun.apply(thisValue, args);\n  };\n}\n\nif (!freeze) {\n  freeze = function (x) {\n    return x;\n  };\n}\n\nif (!seal) {\n  seal = function (x) {\n    return x;\n  };\n}\n\nif (!construct) {\n  construct = function (Func, args) {\n    return new Func(...args);\n  };\n}\n\nconst arrayForEach = unapply(Array.prototype.forEach);\nconst arrayIndexOf = unapply(Array.prototype.indexOf);\nconst arrayPop = unapply(Array.prototype.pop);\nconst arrayPush = unapply(Array.prototype.push);\nconst arraySlice = unapply(Array.prototype.slice);\n\nconst stringToLowerCase = unapply(String.prototype.toLowerCase);\nconst stringToString = unapply(String.prototype.toString);\nconst stringMatch = unapply(String.prototype.match);\nconst stringReplace = unapply(String.prototype.replace);\nconst stringIndexOf = unapply(String.prototype.indexOf);\nconst stringTrim = unapply(String.prototype.trim);\n\nconst regExpTest = unapply(RegExp.prototype.test);\n\nconst typeErrorCreate = unconstruct(TypeError);\n\nexport function unapply(func) {\n  return (thisArg, ...args) => apply(func, thisArg, args);\n}\n\nexport function unconstruct(func) {\n  return (...args) => construct(func, args);\n}\n\n/* Add properties to a lookup table */\nexport function addToSet(set, array, transformCaseFunc) {\n  transformCaseFunc = transformCaseFunc ?? stringToLowerCase;\n  if (setPrototypeOf) {\n    // Make 'in' and truthy checks like Boolean(set.constructor)\n    // independent of any properties defined on Object.prototype.\n    // Prevent prototype setters from intercepting set as a this value.\n    setPrototypeOf(set, null);\n  }\n\n  let l = array.length;\n  while (l--) {\n    let element = array[l];\n    if (typeof element === 'string') {\n      const lcElement = transformCaseFunc(element);\n      if (lcElement !== element) {\n        // Config presets (e.g. tags.js, attrs.js) are immutable.\n        if (!isFrozen(array)) {\n          array[l] = lcElement;\n        }\n\n        element = lcElement;\n      }\n    }\n\n    set[element] = true;\n  }\n\n  return set;\n}\n\n/* Shallow clone an object */\nexport function clone(object) {\n  const newObject = create(null);\n\n  for (const [property, value] of entries(object)) {\n    newObject[property] = value;\n  }\n\n  return newObject;\n}\n\n/* This method automatically checks if the prop is function\n * or getter and behaves accordingly. */\nfunction lookupGetter(object, prop) {\n  while (object !== null) {\n    const desc = getOwnPropertyDescriptor(object, prop);\n    if (desc) {\n      if (desc.get) {\n        return unapply(desc.get);\n      }\n\n      if (typeof desc.value === 'function') {\n        return unapply(desc.value);\n      }\n    }\n\n    object = getPrototypeOf(object);\n  }\n\n  function fallbackValue(element) {\n    console.warn('fallback value for', element);\n    return null;\n  }\n\n  return fallbackValue;\n}\n\nexport {\n  // Array\n  arrayForEach,\n  arrayIndexOf,\n  arrayPop,\n  arrayPush,\n  arraySlice,\n  // Object\n  entries,\n  freeze,\n  getPrototypeOf,\n  getOwnPropertyDescriptor,\n  isFrozen,\n  setPrototypeOf,\n  seal,\n  // RegExp\n  regExpTest,\n  // String\n  stringIndexOf,\n  stringMatch,\n  stringReplace,\n  stringToLowerCase,\n  stringToString,\n  stringTrim,\n  // Errors\n  typeErrorCreate,\n  // Other\n  lookupGetter,\n};\n","import { freeze } from './utils.js';\n\nexport const html = freeze([\n  'a',\n  'abbr',\n  'acronym',\n  'address',\n  'area',\n  'article',\n  'aside',\n  'audio',\n  'b',\n  'bdi',\n  'bdo',\n  'big',\n  'blink',\n  'blockquote',\n  'body',\n  'br',\n  'button',\n  'canvas',\n  'caption',\n  'center',\n  'cite',\n  'code',\n  'col',\n  'colgroup',\n  'content',\n  'data',\n  'datalist',\n  'dd',\n  'decorator',\n  'del',\n  'details',\n  'dfn',\n  'dialog',\n  'dir',\n  'div',\n  'dl',\n  'dt',\n  'element',\n  'em',\n  'fieldset',\n  'figcaption',\n  'figure',\n  'font',\n  'footer',\n  'form',\n  'h1',\n  'h2',\n  'h3',\n  'h4',\n  'h5',\n  'h6',\n  'head',\n  'header',\n  'hgroup',\n  'hr',\n  'html',\n  'i',\n  'img',\n  'input',\n  'ins',\n  'kbd',\n  'label',\n  'legend',\n  'li',\n  'main',\n  'map',\n  'mark',\n  'marquee',\n  'menu',\n  'menuitem',\n  'meter',\n  'nav',\n  'nobr',\n  'ol',\n  'optgroup',\n  'option',\n  'output',\n  'p',\n  'picture',\n  'pre',\n  'progress',\n  'q',\n  'rp',\n  'rt',\n  'ruby',\n  's',\n  'samp',\n  'section',\n  'select',\n  'shadow',\n  'small',\n  'source',\n  'spacer',\n  'span',\n  'strike',\n  'strong',\n  'style',\n  'sub',\n  'summary',\n  'sup',\n  'table',\n  'tbody',\n  'td',\n  'template',\n  'textarea',\n  'tfoot',\n  'th',\n  'thead',\n  'time',\n  'tr',\n  'track',\n  'tt',\n  'u',\n  'ul',\n  'var',\n  'video',\n  'wbr',\n]);\n\n// SVG\nexport const svg = freeze([\n  'svg',\n  'a',\n  'altglyph',\n  'altglyphdef',\n  'altglyphitem',\n  'animatecolor',\n  'animatemotion',\n  'animatetransform',\n  'circle',\n  'clippath',\n  'defs',\n  'desc',\n  'ellipse',\n  'filter',\n  'font',\n  'g',\n  'glyph',\n  'glyphref',\n  'hkern',\n  'image',\n  'line',\n  'lineargradient',\n  'marker',\n  'mask',\n  'metadata',\n  'mpath',\n  'path',\n  'pattern',\n  'polygon',\n  'polyline',\n  'radialgradient',\n  'rect',\n  'stop',\n  'style',\n  'switch',\n  'symbol',\n  'text',\n  'textpath',\n  'title',\n  'tref',\n  'tspan',\n  'view',\n  'vkern',\n]);\n\nexport const svgFilters = freeze([\n  'feBlend',\n  'feColorMatrix',\n  'feComponentTransfer',\n  'feComposite',\n  'feConvolveMatrix',\n  'feDiffuseLighting',\n  'feDisplacementMap',\n  'feDistantLight',\n  'feDropShadow',\n  'feFlood',\n  'feFuncA',\n  'feFuncB',\n  'feFuncG',\n  'feFuncR',\n  'feGaussianBlur',\n  'feImage',\n  'feMerge',\n  'feMergeNode',\n  'feMorphology',\n  'feOffset',\n  'fePointLight',\n  'feSpecularLighting',\n  'feSpotLight',\n  'feTile',\n  'feTurbulence',\n]);\n\n// List of SVG elements that are disallowed by default.\n// We still need to know them so that we can do namespace\n// checks properly in case one wants to add them to\n// allow-list.\nexport const svgDisallowed = freeze([\n  'animate',\n  'color-profile',\n  'cursor',\n  'discard',\n  'font-face',\n  'font-face-format',\n  'font-face-name',\n  'font-face-src',\n  'font-face-uri',\n  'foreignobject',\n  'hatch',\n  'hatchpath',\n  'mesh',\n  'meshgradient',\n  'meshpatch',\n  'meshrow',\n  'missing-glyph',\n  'script',\n  'set',\n  'solidcolor',\n  'unknown',\n  'use',\n]);\n\nexport const mathMl = freeze([\n  'math',\n  'menclose',\n  'merror',\n  'mfenced',\n  'mfrac',\n  'mglyph',\n  'mi',\n  'mlabeledtr',\n  'mmultiscripts',\n  'mn',\n  'mo',\n  'mover',\n  'mpadded',\n  'mphantom',\n  'mroot',\n  'mrow',\n  'ms',\n  'mspace',\n  'msqrt',\n  'mstyle',\n  'msub',\n  'msup',\n  'msubsup',\n  'mtable',\n  'mtd',\n  'mtext',\n  'mtr',\n  'munder',\n  'munderover',\n  'mprescripts',\n]);\n\n// Similarly to SVG, we want to know all MathML elements,\n// even those that we disallow by default.\nexport const mathMlDisallowed = freeze([\n  'maction',\n  'maligngroup',\n  'malignmark',\n  'mlongdiv',\n  'mscarries',\n  'mscarry',\n  'msgroup',\n  'mstack',\n  'msline',\n  'msrow',\n  'semantics',\n  'annotation',\n  'annotation-xml',\n  'mprescripts',\n  'none',\n]);\n\nexport const text = freeze(['#text']);\n","import { freeze } from './utils.js';\n\nexport const html = freeze([\n  'accept',\n  'action',\n  'align',\n  'alt',\n  'autocapitalize',\n  'autocomplete',\n  'autopictureinpicture',\n  'autoplay',\n  'background',\n  'bgcolor',\n  'border',\n  'capture',\n  'cellpadding',\n  'cellspacing',\n  'checked',\n  'cite',\n  'class',\n  'clear',\n  'color',\n  'cols',\n  'colspan',\n  'controls',\n  'controlslist',\n  'coords',\n  'crossorigin',\n  'datetime',\n  'decoding',\n  'default',\n  'dir',\n  'disabled',\n  'disablepictureinpicture',\n  'disableremoteplayback',\n  'download',\n  'draggable',\n  'enctype',\n  'enterkeyhint',\n  'face',\n  'for',\n  'headers',\n  'height',\n  'hidden',\n  'high',\n  'href',\n  'hreflang',\n  'id',\n  'inputmode',\n  'integrity',\n  'ismap',\n  'kind',\n  'label',\n  'lang',\n  'list',\n  'loading',\n  'loop',\n  'low',\n  'max',\n  'maxlength',\n  'media',\n  'method',\n  'min',\n  'minlength',\n  'multiple',\n  'muted',\n  'name',\n  'nonce',\n  'noshade',\n  'novalidate',\n  'nowrap',\n  'open',\n  'optimum',\n  'pattern',\n  'placeholder',\n  'playsinline',\n  'poster',\n  'preload',\n  'pubdate',\n  'radiogroup',\n  'readonly',\n  'rel',\n  'required',\n  'rev',\n  'reversed',\n  'role',\n  'rows',\n  'rowspan',\n  'spellcheck',\n  'scope',\n  'selected',\n  'shape',\n  'size',\n  'sizes',\n  'span',\n  'srclang',\n  'start',\n  'src',\n  'srcset',\n  'step',\n  'style',\n  'summary',\n  'tabindex',\n  'title',\n  'translate',\n  'type',\n  'usemap',\n  'valign',\n  'value',\n  'width',\n  'xmlns',\n  'slot',\n]);\n\nexport const svg = freeze([\n  'accent-height',\n  'accumulate',\n  'additive',\n  'alignment-baseline',\n  'ascent',\n  'attributename',\n  'attributetype',\n  'azimuth',\n  'basefrequency',\n  'baseline-shift',\n  'begin',\n  'bias',\n  'by',\n  'class',\n  'clip',\n  'clippathunits',\n  'clip-path',\n  'clip-rule',\n  'color',\n  'color-interpolation',\n  'color-interpolation-filters',\n  'color-profile',\n  'color-rendering',\n  'cx',\n  'cy',\n  'd',\n  'dx',\n  'dy',\n  'diffuseconstant',\n  'direction',\n  'display',\n  'divisor',\n  'dur',\n  'edgemode',\n  'elevation',\n  'end',\n  'fill',\n  'fill-opacity',\n  'fill-rule',\n  'filter',\n  'filterunits',\n  'flood-color',\n  'flood-opacity',\n  'font-family',\n  'font-size',\n  'font-size-adjust',\n  'font-stretch',\n  'font-style',\n  'font-variant',\n  'font-weight',\n  'fx',\n  'fy',\n  'g1',\n  'g2',\n  'glyph-name',\n  'glyphref',\n  'gradientunits',\n  'gradienttransform',\n  'height',\n  'href',\n  'id',\n  'image-rendering',\n  'in',\n  'in2',\n  'k',\n  'k1',\n  'k2',\n  'k3',\n  'k4',\n  'kerning',\n  'keypoints',\n  'keysplines',\n  'keytimes',\n  'lang',\n  'lengthadjust',\n  'letter-spacing',\n  'kernelmatrix',\n  'kernelunitlength',\n  'lighting-color',\n  'local',\n  'marker-end',\n  'marker-mid',\n  'marker-start',\n  'markerheight',\n  'markerunits',\n  'markerwidth',\n  'maskcontentunits',\n  'maskunits',\n  'max',\n  'mask',\n  'media',\n  'method',\n  'mode',\n  'min',\n  'name',\n  'numoctaves',\n  'offset',\n  'operator',\n  'opacity',\n  'order',\n  'orient',\n  'orientation',\n  'origin',\n  'overflow',\n  'paint-order',\n  'path',\n  'pathlength',\n  'patterncontentunits',\n  'patterntransform',\n  'patternunits',\n  'points',\n  'preservealpha',\n  'preserveaspectratio',\n  'primitiveunits',\n  'r',\n  'rx',\n  'ry',\n  'radius',\n  'refx',\n  'refy',\n  'repeatcount',\n  'repeatdur',\n  'restart',\n  'result',\n  'rotate',\n  'scale',\n  'seed',\n  'shape-rendering',\n  'specularconstant',\n  'specularexponent',\n  'spreadmethod',\n  'startoffset',\n  'stddeviation',\n  'stitchtiles',\n  'stop-color',\n  'stop-opacity',\n  'stroke-dasharray',\n  'stroke-dashoffset',\n  'stroke-linecap',\n  'stroke-linejoin',\n  'stroke-miterlimit',\n  'stroke-opacity',\n  'stroke',\n  'stroke-width',\n  'style',\n  'surfacescale',\n  'systemlanguage',\n  'tabindex',\n  'targetx',\n  'targety',\n  'transform',\n  'transform-origin',\n  'text-anchor',\n  'text-decoration',\n  'text-rendering',\n  'textlength',\n  'type',\n  'u1',\n  'u2',\n  'unicode',\n  'values',\n  'viewbox',\n  'visibility',\n  'version',\n  'vert-adv-y',\n  'vert-origin-x',\n  'vert-origin-y',\n  'width',\n  'word-spacing',\n  'wrap',\n  'writing-mode',\n  'xchannelselector',\n  'ychannelselector',\n  'x',\n  'x1',\n  'x2',\n  'xmlns',\n  'y',\n  'y1',\n  'y2',\n  'z',\n  'zoomandpan',\n]);\n\nexport const mathMl = freeze([\n  'accent',\n  'accentunder',\n  'align',\n  'bevelled',\n  'close',\n  'columnsalign',\n  'columnlines',\n  'columnspan',\n  'denomalign',\n  'depth',\n  'dir',\n  'display',\n  'displaystyle',\n  'encoding',\n  'fence',\n  'frame',\n  'height',\n  'href',\n  'id',\n  'largeop',\n  'length',\n  'linethickness',\n  'lspace',\n  'lquote',\n  'mathbackground',\n  'mathcolor',\n  'mathsize',\n  'mathvariant',\n  'maxsize',\n  'minsize',\n  'movablelimits',\n  'notation',\n  'numalign',\n  'open',\n  'rowalign',\n  'rowlines',\n  'rowspacing',\n  'rowspan',\n  'rspace',\n  'rquote',\n  'scriptlevel',\n  'scriptminsize',\n  'scriptsizemultiplier',\n  'selection',\n  'separator',\n  'separators',\n  'stretchy',\n  'subscriptshift',\n  'supscriptshift',\n  'symmetric',\n  'voffset',\n  'width',\n  'xmlns',\n]);\n\nexport const xml = freeze([\n  'xlink:href',\n  'xml:id',\n  'xlink:title',\n  'xml:space',\n  'xmlns:xlink',\n]);\n","import { seal } from './utils.js';\n\n// eslint-disable-next-line unicorn/better-regex\nexport const MUSTACHE_EXPR = seal(/\\{\\{[\\w\\W]*|[\\w\\W]*\\}\\}/gm); // Specify template detection regex for SAFE_FOR_TEMPLATES mode\nexport const ERB_EXPR = seal(/<%[\\w\\W]*|[\\w\\W]*%>/gm);\nexport const TMPLIT_EXPR = seal(/\\${[\\w\\W]*}/gm);\nexport const DATA_ATTR = seal(/^data-[\\-\\w.\\u00B7-\\uFFFF]/); // eslint-disable-line no-useless-escape\nexport const ARIA_ATTR = seal(/^aria-[\\-\\w]+$/); // eslint-disable-line no-useless-escape\nexport const IS_ALLOWED_URI = seal(\n  /^(?:(?:(?:f|ht)tps?|mailto|tel|callto|sms|cid|xmpp):|[^a-z]|[a-z+.\\-]+(?:[^a-z+.\\-:]|$))/i // eslint-disable-line no-useless-escape\n);\nexport const IS_SCRIPT_OR_DATA = seal(/^(?:\\w+script|data):/i);\nexport const ATTR_WHITESPACE = seal(\n  /[\\u0000-\\u0020\\u00A0\\u1680\\u180E\\u2000-\\u2029\\u205F\\u3000]/g // eslint-disable-line no-control-regex\n);\nexport const DOCTYPE_NAME = seal(/^html$/i);\n","import * as TAGS from './tags.js';\nimport * as ATTRS from './attrs.js';\nimport * as EXPRESSIONS from './regexp.js';\nimport {\n  addToSet,\n  clone,\n  entries,\n  freeze,\n  arrayForEach,\n  arrayPop,\n  arrayPush,\n  stringMatch,\n  stringReplace,\n  stringToLowerCase,\n  stringToString,\n  stringIndexOf,\n  stringTrim,\n  regExpTest,\n  typeErrorCreate,\n  lookupGetter,\n} from './utils.js';\n\nconst getGlobal = () => (typeof window === 'undefined' ? null : window);\n\n/**\n * Creates a no-op policy for internal use only.\n * Don't export this function outside this module!\n * @param {?TrustedTypePolicyFactory} trustedTypes The policy factory.\n * @param {HTMLScriptElement} purifyHostElement The Script element used to load DOMPurify (to determine policy name suffix).\n * @return {?TrustedTypePolicy} The policy created (or null, if Trusted Types\n * are not supported or creating the policy failed).\n */\nconst _createTrustedTypesPolicy = function (trustedTypes, purifyHostElement) {\n  if (\n    typeof trustedTypes !== 'object' ||\n    typeof trustedTypes.createPolicy !== 'function'\n  ) {\n    return null;\n  }\n\n  // Allow the callers to control the unique policy name\n  // by adding a data-tt-policy-suffix to the script element with the DOMPurify.\n  // Policy creation with duplicate names throws in Trusted Types.\n  let suffix = null;\n  const ATTR_NAME = 'data-tt-policy-suffix';\n  if (purifyHostElement && purifyHostElement.hasAttribute(ATTR_NAME)) {\n    suffix = purifyHostElement.getAttribute(ATTR_NAME);\n  }\n\n  const policyName = 'dompurify' + (suffix ? '#' + suffix : '');\n\n  try {\n    return trustedTypes.createPolicy(policyName, {\n      createHTML(html) {\n        return html;\n      },\n      createScriptURL(scriptUrl) {\n        return scriptUrl;\n      },\n    });\n  } catch (_) {\n    // Policy creation failed (most likely another DOMPurify script has\n    // already run). Skip creating the policy, as this will only cause errors\n    // if TT are enforced.\n    console.warn(\n      'TrustedTypes policy ' + policyName + ' could not be created.'\n    );\n    return null;\n  }\n};\n\nfunction createDOMPurify(window = getGlobal()) {\n  const DOMPurify = (root) => createDOMPurify(root);\n\n  /**\n   * Version label, exposed for easier checks\n   * if DOMPurify is up to date or not\n   */\n  DOMPurify.version = VERSION;\n\n  /**\n   * Array of elements that DOMPurify removed during sanitation.\n   * Empty if nothing was removed.\n   */\n  DOMPurify.removed = [];\n\n  if (!window || !window.document || window.document.nodeType !== 9) {\n    // Not running in a browser, provide a factory function\n    // so that you can pass your own Window\n    DOMPurify.isSupported = false;\n\n    return DOMPurify;\n  }\n\n  const originalDocument = window.document;\n  const currentScript = originalDocument.currentScript;\n\n  let { document } = window;\n  const {\n    DocumentFragment,\n    HTMLTemplateElement,\n    Node,\n    Element,\n    NodeFilter,\n    NamedNodeMap = window.NamedNodeMap || window.MozNamedAttrMap,\n    HTMLFormElement,\n    DOMParser,\n    trustedTypes,\n  } = window;\n\n  const ElementPrototype = Element.prototype;\n\n  const cloneNode = lookupGetter(ElementPrototype, 'cloneNode');\n  const getNextSibling = lookupGetter(ElementPrototype, 'nextSibling');\n  const getChildNodes = lookupGetter(ElementPrototype, 'childNodes');\n  const getParentNode = lookupGetter(ElementPrototype, 'parentNode');\n\n  // As per issue #47, the web-components registry is inherited by a\n  // new document created via createHTMLDocument. As per the spec\n  // (http://w3c.github.io/webcomponents/spec/custom/#creating-and-passing-registries)\n  // a new empty registry is used when creating a template contents owner\n  // document, so we use that as our parent document to ensure nothing\n  // is inherited.\n  if (typeof HTMLTemplateElement === 'function') {\n    const template = document.createElement('template');\n    if (template.content && template.content.ownerDocument) {\n      document = template.content.ownerDocument;\n    }\n  }\n\n  let trustedTypesPolicy;\n  let emptyHTML = '';\n\n  const {\n    implementation,\n    createNodeIterator,\n    createDocumentFragment,\n    getElementsByTagName,\n  } = document;\n  const { importNode } = originalDocument;\n\n  let hooks = {};\n\n  /**\n   * Expose whether this browser supports running the full DOMPurify.\n   */\n  DOMPurify.isSupported =\n    typeof entries === 'function' &&\n    typeof getParentNode === 'function' &&\n    implementation &&\n    implementation.createHTMLDocument !== undefined;\n\n  const {\n    MUSTACHE_EXPR,\n    ERB_EXPR,\n    TMPLIT_EXPR,\n    DATA_ATTR,\n    ARIA_ATTR,\n    IS_SCRIPT_OR_DATA,\n    ATTR_WHITESPACE,\n  } = EXPRESSIONS;\n\n  let { IS_ALLOWED_URI } = EXPRESSIONS;\n\n  /**\n   * We consider the elements and attributes below to be safe. Ideally\n   * don't add any new ones but feel free to remove unwanted ones.\n   */\n\n  /* allowed element names */\n  let ALLOWED_TAGS = null;\n  const DEFAULT_ALLOWED_TAGS = addToSet({}, [\n    ...TAGS.html,\n    ...TAGS.svg,\n    ...TAGS.svgFilters,\n    ...TAGS.mathMl,\n    ...TAGS.text,\n  ]);\n\n  /* Allowed attribute names */\n  let ALLOWED_ATTR = null;\n  const DEFAULT_ALLOWED_ATTR = addToSet({}, [\n    ...ATTRS.html,\n    ...ATTRS.svg,\n    ...ATTRS.mathMl,\n    ...ATTRS.xml,\n  ]);\n\n  /*\n   * Configure how DOMPUrify should handle custom elements and their attributes as well as customized built-in elements.\n   * @property {RegExp|Function|null} tagNameCheck one of [null, regexPattern, predicate]. Default: `null` (disallow any custom elements)\n   * @property {RegExp|Function|null} attributeNameCheck one of [null, regexPattern, predicate]. Default: `null` (disallow any attributes not on the allow list)\n   * @property {boolean} allowCustomizedBuiltInElements allow custom elements derived from built-ins if they pass CUSTOM_ELEMENT_HANDLING.tagNameCheck. Default: `false`.\n   */\n  let CUSTOM_ELEMENT_HANDLING = Object.seal(\n    Object.create(null, {\n      tagNameCheck: {\n        writable: true,\n        configurable: false,\n        enumerable: true,\n        value: null,\n      },\n      attributeNameCheck: {\n        writable: true,\n        configurable: false,\n        enumerable: true,\n        value: null,\n      },\n      allowCustomizedBuiltInElements: {\n        writable: true,\n        configurable: false,\n        enumerable: true,\n        value: false,\n      },\n    })\n  );\n\n  /* Explicitly forbidden tags (overrides ALLOWED_TAGS/ADD_TAGS) */\n  let FORBID_TAGS = null;\n\n  /* Explicitly forbidden attributes (overrides ALLOWED_ATTR/ADD_ATTR) */\n  let FORBID_ATTR = null;\n\n  /* Decide if ARIA attributes are okay */\n  let ALLOW_ARIA_ATTR = true;\n\n  /* Decide if custom data attributes are okay */\n  let ALLOW_DATA_ATTR = true;\n\n  /* Decide if unknown protocols are okay */\n  let ALLOW_UNKNOWN_PROTOCOLS = false;\n\n  /* Decide if self-closing tags in attributes are allowed.\n   * Usually removed due to a mXSS issue in jQuery 3.0 */\n  let ALLOW_SELF_CLOSE_IN_ATTR = true;\n\n  /* Output should be safe for common template engines.\n   * This means, DOMPurify removes data attributes, mustaches and ERB\n   */\n  let SAFE_FOR_TEMPLATES = false;\n\n  /* Decide if document with <html>... should be returned */\n  let WHOLE_DOCUMENT = false;\n\n  /* Track whether config is already set on this instance of DOMPurify. */\n  let SET_CONFIG = false;\n\n  /* Decide if all elements (e.g. style, script) must be children of\n   * document.body. By default, browsers might move them to document.head */\n  let FORCE_BODY = false;\n\n  /* Decide if a DOM `HTMLBodyElement` should be returned, instead of a html\n   * string (or a TrustedHTML object if Trusted Types are supported).\n   * If `WHOLE_DOCUMENT` is enabled a `HTMLHtmlElement` will be returned instead\n   */\n  let RETURN_DOM = false;\n\n  /* Decide if a DOM `DocumentFragment` should be returned, instead of a html\n   * string  (or a TrustedHTML object if Trusted Types are supported) */\n  let RETURN_DOM_FRAGMENT = false;\n\n  /* Try to return a Trusted Type object instead of a string, return a string in\n   * case Trusted Types are not supported  */\n  let RETURN_TRUSTED_TYPE = false;\n\n  /* Output should be free from DOM clobbering attacks?\n   * This sanitizes markups named with colliding, clobberable built-in DOM APIs.\n   */\n  let SANITIZE_DOM = true;\n\n  /* Achieve full DOM Clobbering protection by isolating the namespace of named\n   * properties and JS variables, mitigating attacks that abuse the HTML/DOM spec rules.\n   *\n   * HTML/DOM spec rules that enable DOM Clobbering:\n   *   - Named Access on Window (§7.3.3)\n   *   - DOM Tree Accessors (§3.1.5)\n   *   - Form Element Parent-Child Relations (§4.10.3)\n   *   - Iframe srcdoc / Nested WindowProxies (§4.8.5)\n   *   - HTMLCollection (§4.2.10.2)\n   *\n   * Namespace isolation is implemented by prefixing `id` and `name` attributes\n   * with a constant string, i.e., `user-content-`\n   */\n  let SANITIZE_NAMED_PROPS = false;\n  const SANITIZE_NAMED_PROPS_PREFIX = 'user-content-';\n\n  /* Keep element content when removing element? */\n  let KEEP_CONTENT = true;\n\n  /* If a `Node` is passed to sanitize(), then performs sanitization in-place instead\n   * of importing it into a new Document and returning a sanitized copy */\n  let IN_PLACE = false;\n\n  /* Allow usage of profiles like html, svg and mathMl */\n  let USE_PROFILES = {};\n\n  /* Tags to ignore content of when KEEP_CONTENT is true */\n  let FORBID_CONTENTS = null;\n  const DEFAULT_FORBID_CONTENTS = addToSet({}, [\n    'annotation-xml',\n    'audio',\n    'colgroup',\n    'desc',\n    'foreignobject',\n    'head',\n    'iframe',\n    'math',\n    'mi',\n    'mn',\n    'mo',\n    'ms',\n    'mtext',\n    'noembed',\n    'noframes',\n    'noscript',\n    'plaintext',\n    'script',\n    'style',\n    'svg',\n    'template',\n    'thead',\n    'title',\n    'video',\n    'xmp',\n  ]);\n\n  /* Tags that are safe for data: URIs */\n  let DATA_URI_TAGS = null;\n  const DEFAULT_DATA_URI_TAGS = addToSet({}, [\n    'audio',\n    'video',\n    'img',\n    'source',\n    'image',\n    'track',\n  ]);\n\n  /* Attributes safe for values like \"javascript:\" */\n  let URI_SAFE_ATTRIBUTES = null;\n  const DEFAULT_URI_SAFE_ATTRIBUTES = addToSet({}, [\n    'alt',\n    'class',\n    'for',\n    'id',\n    'label',\n    'name',\n    'pattern',\n    'placeholder',\n    'role',\n    'summary',\n    'title',\n    'value',\n    'style',\n    'xmlns',\n  ]);\n\n  const MATHML_NAMESPACE = 'http://www.w3.org/1998/Math/MathML';\n  const SVG_NAMESPACE = 'http://www.w3.org/2000/svg';\n  const HTML_NAMESPACE = 'http://www.w3.org/1999/xhtml';\n  /* Document namespace */\n  let NAMESPACE = HTML_NAMESPACE;\n  let IS_EMPTY_INPUT = false;\n\n  /* Allowed XHTML+XML namespaces */\n  let ALLOWED_NAMESPACES = null;\n  const DEFAULT_ALLOWED_NAMESPACES = addToSet(\n    {},\n    [MATHML_NAMESPACE, SVG_NAMESPACE, HTML_NAMESPACE],\n    stringToString\n  );\n\n  /* Parsing of strict XHTML documents */\n  let PARSER_MEDIA_TYPE;\n  const SUPPORTED_PARSER_MEDIA_TYPES = ['application/xhtml+xml', 'text/html'];\n  const DEFAULT_PARSER_MEDIA_TYPE = 'text/html';\n  let transformCaseFunc;\n\n  /* Keep a reference to config to pass to hooks */\n  let CONFIG = null;\n\n  /* Ideally, do not touch anything below this line */\n  /* ______________________________________________ */\n\n  const formElement = document.createElement('form');\n\n  const isRegexOrFunction = function (testValue) {\n    return testValue instanceof RegExp || testValue instanceof Function;\n  };\n\n  /**\n   * _parseConfig\n   *\n   * @param  {Object} cfg optional config literal\n   */\n  // eslint-disable-next-line complexity\n  const _parseConfig = function (cfg) {\n    if (CONFIG && CONFIG === cfg) {\n      return;\n    }\n\n    /* Shield configuration object from tampering */\n    if (!cfg || typeof cfg !== 'object') {\n      cfg = {};\n    }\n\n    /* Shield configuration object from prototype pollution */\n    cfg = clone(cfg);\n\n    PARSER_MEDIA_TYPE =\n      // eslint-disable-next-line unicorn/prefer-includes\n      SUPPORTED_PARSER_MEDIA_TYPES.indexOf(cfg.PARSER_MEDIA_TYPE) === -1\n        ? (PARSER_MEDIA_TYPE = DEFAULT_PARSER_MEDIA_TYPE)\n        : (PARSER_MEDIA_TYPE = cfg.PARSER_MEDIA_TYPE);\n\n    // HTML tags and attributes are not case-sensitive, converting to lowercase. Keeping XHTML as is.\n    transformCaseFunc =\n      PARSER_MEDIA_TYPE === 'application/xhtml+xml'\n        ? stringToString\n        : stringToLowerCase;\n\n    /* Set configuration parameters */\n    ALLOWED_TAGS =\n      'ALLOWED_TAGS' in cfg\n        ? addToSet({}, cfg.ALLOWED_TAGS, transformCaseFunc)\n        : DEFAULT_ALLOWED_TAGS;\n    ALLOWED_ATTR =\n      'ALLOWED_ATTR' in cfg\n        ? addToSet({}, cfg.ALLOWED_ATTR, transformCaseFunc)\n        : DEFAULT_ALLOWED_ATTR;\n    ALLOWED_NAMESPACES =\n      'ALLOWED_NAMESPACES' in cfg\n        ? addToSet({}, cfg.ALLOWED_NAMESPACES, stringToString)\n        : DEFAULT_ALLOWED_NAMESPACES;\n    URI_SAFE_ATTRIBUTES =\n      'ADD_URI_SAFE_ATTR' in cfg\n        ? addToSet(\n            clone(DEFAULT_URI_SAFE_ATTRIBUTES), // eslint-disable-line indent\n            cfg.ADD_URI_SAFE_ATTR, // eslint-disable-line indent\n            transformCaseFunc // eslint-disable-line indent\n          ) // eslint-disable-line indent\n        : DEFAULT_URI_SAFE_ATTRIBUTES;\n    DATA_URI_TAGS =\n      'ADD_DATA_URI_TAGS' in cfg\n        ? addToSet(\n            clone(DEFAULT_DATA_URI_TAGS), // eslint-disable-line indent\n            cfg.ADD_DATA_URI_TAGS, // eslint-disable-line indent\n            transformCaseFunc // eslint-disable-line indent\n          ) // eslint-disable-line indent\n        : DEFAULT_DATA_URI_TAGS;\n    FORBID_CONTENTS =\n      'FORBID_CONTENTS' in cfg\n        ? addToSet({}, cfg.FORBID_CONTENTS, transformCaseFunc)\n        : DEFAULT_FORBID_CONTENTS;\n    FORBID_TAGS =\n      'FORBID_TAGS' in cfg\n        ? addToSet({}, cfg.FORBID_TAGS, transformCaseFunc)\n        : {};\n    FORBID_ATTR =\n      'FORBID_ATTR' in cfg\n        ? addToSet({}, cfg.FORBID_ATTR, transformCaseFunc)\n        : {};\n    USE_PROFILES = 'USE_PROFILES' in cfg ? cfg.USE_PROFILES : false;\n    ALLOW_ARIA_ATTR = cfg.ALLOW_ARIA_ATTR !== false; // Default true\n    ALLOW_DATA_ATTR = cfg.ALLOW_DATA_ATTR !== false; // Default true\n    ALLOW_UNKNOWN_PROTOCOLS = cfg.ALLOW_UNKNOWN_PROTOCOLS || false; // Default false\n    ALLOW_SELF_CLOSE_IN_ATTR = cfg.ALLOW_SELF_CLOSE_IN_ATTR !== false; // Default true\n    SAFE_FOR_TEMPLATES = cfg.SAFE_FOR_TEMPLATES || false; // Default false\n    WHOLE_DOCUMENT = cfg.WHOLE_DOCUMENT || false; // Default false\n    RETURN_DOM = cfg.RETURN_DOM || false; // Default false\n    RETURN_DOM_FRAGMENT = cfg.RETURN_DOM_FRAGMENT || false; // Default false\n    RETURN_TRUSTED_TYPE = cfg.RETURN_TRUSTED_TYPE || false; // Default false\n    FORCE_BODY = cfg.FORCE_BODY || false; // Default false\n    SANITIZE_DOM = cfg.SANITIZE_DOM !== false; // Default true\n    SANITIZE_NAMED_PROPS = cfg.SANITIZE_NAMED_PROPS || false; // Default false\n    KEEP_CONTENT = cfg.KEEP_CONTENT !== false; // Default true\n    IN_PLACE = cfg.IN_PLACE || false; // Default false\n    IS_ALLOWED_URI = cfg.ALLOWED_URI_REGEXP || EXPRESSIONS.IS_ALLOWED_URI;\n    NAMESPACE = cfg.NAMESPACE || HTML_NAMESPACE;\n    CUSTOM_ELEMENT_HANDLING = cfg.CUSTOM_ELEMENT_HANDLING || {};\n    if (\n      cfg.CUSTOM_ELEMENT_HANDLING &&\n      isRegexOrFunction(cfg.CUSTOM_ELEMENT_HANDLING.tagNameCheck)\n    ) {\n      CUSTOM_ELEMENT_HANDLING.tagNameCheck =\n        cfg.CUSTOM_ELEMENT_HANDLING.tagNameCheck;\n    }\n\n    if (\n      cfg.CUSTOM_ELEMENT_HANDLING &&\n      isRegexOrFunction(cfg.CUSTOM_ELEMENT_HANDLING.attributeNameCheck)\n    ) {\n      CUSTOM_ELEMENT_HANDLING.attributeNameCheck =\n        cfg.CUSTOM_ELEMENT_HANDLING.attributeNameCheck;\n    }\n\n    if (\n      cfg.CUSTOM_ELEMENT_HANDLING &&\n      typeof cfg.CUSTOM_ELEMENT_HANDLING.allowCustomizedBuiltInElements ===\n        'boolean'\n    ) {\n      CUSTOM_ELEMENT_HANDLING.allowCustomizedBuiltInElements =\n        cfg.CUSTOM_ELEMENT_HANDLING.allowCustomizedBuiltInElements;\n    }\n\n    if (SAFE_FOR_TEMPLATES) {\n      ALLOW_DATA_ATTR = false;\n    }\n\n    if (RETURN_DOM_FRAGMENT) {\n      RETURN_DOM = true;\n    }\n\n    /* Parse profile info */\n    if (USE_PROFILES) {\n      ALLOWED_TAGS = addToSet({}, [...TAGS.text]);\n      ALLOWED_ATTR = [];\n      if (USE_PROFILES.html === true) {\n        addToSet(ALLOWED_TAGS, TAGS.html);\n        addToSet(ALLOWED_ATTR, ATTRS.html);\n      }\n\n      if (USE_PROFILES.svg === true) {\n        addToSet(ALLOWED_TAGS, TAGS.svg);\n        addToSet(ALLOWED_ATTR, ATTRS.svg);\n        addToSet(ALLOWED_ATTR, ATTRS.xml);\n      }\n\n      if (USE_PROFILES.svgFilters === true) {\n        addToSet(ALLOWED_TAGS, TAGS.svgFilters);\n        addToSet(ALLOWED_ATTR, ATTRS.svg);\n        addToSet(ALLOWED_ATTR, ATTRS.xml);\n      }\n\n      if (USE_PROFILES.mathMl === true) {\n        addToSet(ALLOWED_TAGS, TAGS.mathMl);\n        addToSet(ALLOWED_ATTR, ATTRS.mathMl);\n        addToSet(ALLOWED_ATTR, ATTRS.xml);\n      }\n    }\n\n    /* Merge configuration parameters */\n    if (cfg.ADD_TAGS) {\n      if (ALLOWED_TAGS === DEFAULT_ALLOWED_TAGS) {\n        ALLOWED_TAGS = clone(ALLOWED_TAGS);\n      }\n\n      addToSet(ALLOWED_TAGS, cfg.ADD_TAGS, transformCaseFunc);\n    }\n\n    if (cfg.ADD_ATTR) {\n      if (ALLOWED_ATTR === DEFAULT_ALLOWED_ATTR) {\n        ALLOWED_ATTR = clone(ALLOWED_ATTR);\n      }\n\n      addToSet(ALLOWED_ATTR, cfg.ADD_ATTR, transformCaseFunc);\n    }\n\n    if (cfg.ADD_URI_SAFE_ATTR) {\n      addToSet(URI_SAFE_ATTRIBUTES, cfg.ADD_URI_SAFE_ATTR, transformCaseFunc);\n    }\n\n    if (cfg.FORBID_CONTENTS) {\n      if (FORBID_CONTENTS === DEFAULT_FORBID_CONTENTS) {\n        FORBID_CONTENTS = clone(FORBID_CONTENTS);\n      }\n\n      addToSet(FORBID_CONTENTS, cfg.FORBID_CONTENTS, transformCaseFunc);\n    }\n\n    /* Add #text in case KEEP_CONTENT is set to true */\n    if (KEEP_CONTENT) {\n      ALLOWED_TAGS['#text'] = true;\n    }\n\n    /* Add html, head and body to ALLOWED_TAGS in case WHOLE_DOCUMENT is true */\n    if (WHOLE_DOCUMENT) {\n      addToSet(ALLOWED_TAGS, ['html', 'head', 'body']);\n    }\n\n    /* Add tbody to ALLOWED_TAGS in case tables are permitted, see #286, #365 */\n    if (ALLOWED_TAGS.table) {\n      addToSet(ALLOWED_TAGS, ['tbody']);\n      delete FORBID_TAGS.tbody;\n    }\n\n    if (cfg.TRUSTED_TYPES_POLICY) {\n      if (typeof cfg.TRUSTED_TYPES_POLICY.createHTML !== 'function') {\n        throw typeErrorCreate(\n          'TRUSTED_TYPES_POLICY configuration option must provide a \"createHTML\" hook.'\n        );\n      }\n\n      if (typeof cfg.TRUSTED_TYPES_POLICY.createScriptURL !== 'function') {\n        throw typeErrorCreate(\n          'TRUSTED_TYPES_POLICY configuration option must provide a \"createScriptURL\" hook.'\n        );\n      }\n\n      // Overwrite existing TrustedTypes policy.\n      trustedTypesPolicy = cfg.TRUSTED_TYPES_POLICY;\n\n      // Sign local variables required by `sanitize`.\n      emptyHTML = trustedTypesPolicy.createHTML('');\n    } else {\n      // Uninitialized policy, attempt to initialize the internal dompurify policy.\n      if (trustedTypesPolicy === undefined) {\n        trustedTypesPolicy = _createTrustedTypesPolicy(\n          trustedTypes,\n          currentScript\n        );\n      }\n\n      // If creating the internal policy succeeded sign internal variables.\n      if (trustedTypesPolicy !== null && typeof emptyHTML === 'string') {\n        emptyHTML = trustedTypesPolicy.createHTML('');\n      }\n    }\n\n    // Prevent further manipulation of configuration.\n    // Not available in IE8, Safari 5, etc.\n    if (freeze) {\n      freeze(cfg);\n    }\n\n    CONFIG = cfg;\n  };\n\n  const MATHML_TEXT_INTEGRATION_POINTS = addToSet({}, [\n    'mi',\n    'mo',\n    'mn',\n    'ms',\n    'mtext',\n  ]);\n\n  const HTML_INTEGRATION_POINTS = addToSet({}, [\n    'foreignobject',\n    'desc',\n    'title',\n    'annotation-xml',\n  ]);\n\n  // Certain elements are allowed in both SVG and HTML\n  // namespace. We need to specify them explicitly\n  // so that they don't get erroneously deleted from\n  // HTML namespace.\n  const COMMON_SVG_AND_HTML_ELEMENTS = addToSet({}, [\n    'title',\n    'style',\n    'font',\n    'a',\n    'script',\n  ]);\n\n  /* Keep track of all possible SVG and MathML tags\n   * so that we can perform the namespace checks\n   * correctly. */\n  const ALL_SVG_TAGS = addToSet({}, TAGS.svg);\n  addToSet(ALL_SVG_TAGS, TAGS.svgFilters);\n  addToSet(ALL_SVG_TAGS, TAGS.svgDisallowed);\n\n  const ALL_MATHML_TAGS = addToSet({}, TAGS.mathMl);\n  addToSet(ALL_MATHML_TAGS, TAGS.mathMlDisallowed);\n\n  /**\n   *\n   *\n   * @param  {Element} element a DOM element whose namespace is being checked\n   * @returns {boolean} Return false if the element has a\n   *  namespace that a spec-compliant parser would never\n   *  return. Return true otherwise.\n   */\n  const _checkValidNamespace = function (element) {\n    let parent = getParentNode(element);\n\n    // In JSDOM, if we're inside shadow DOM, then parentNode\n    // can be null. We just simulate parent in this case.\n    if (!parent || !parent.tagName) {\n      parent = {\n        namespaceURI: NAMESPACE,\n        tagName: 'template',\n      };\n    }\n\n    const tagName = stringToLowerCase(element.tagName);\n    const parentTagName = stringToLowerCase(parent.tagName);\n\n    if (!ALLOWED_NAMESPACES[element.namespaceURI]) {\n      return false;\n    }\n\n    if (element.namespaceURI === SVG_NAMESPACE) {\n      // The only way to switch from HTML namespace to SVG\n      // is via <svg>. If it happens via any other tag, then\n      // it should be killed.\n      if (parent.namespaceURI === HTML_NAMESPACE) {\n        return tagName === 'svg';\n      }\n\n      // The only way to switch from MathML to SVG is via`\n      // svg if parent is either <annotation-xml> or MathML\n      // text integration points.\n      if (parent.namespaceURI === MATHML_NAMESPACE) {\n        return (\n          tagName === 'svg' &&\n          (parentTagName === 'annotation-xml' ||\n            MATHML_TEXT_INTEGRATION_POINTS[parentTagName])\n        );\n      }\n\n      // We only allow elements that are defined in SVG\n      // spec. All others are disallowed in SVG namespace.\n      return Boolean(ALL_SVG_TAGS[tagName]);\n    }\n\n    if (element.namespaceURI === MATHML_NAMESPACE) {\n      // The only way to switch from HTML namespace to MathML\n      // is via <math>. If it happens via any other tag, then\n      // it should be killed.\n      if (parent.namespaceURI === HTML_NAMESPACE) {\n        return tagName === 'math';\n      }\n\n      // The only way to switch from SVG to MathML is via\n      // <math> and HTML integration points\n      if (parent.namespaceURI === SVG_NAMESPACE) {\n        return tagName === 'math' && HTML_INTEGRATION_POINTS[parentTagName];\n      }\n\n      // We only allow elements that are defined in MathML\n      // spec. All others are disallowed in MathML namespace.\n      return Boolean(ALL_MATHML_TAGS[tagName]);\n    }\n\n    if (element.namespaceURI === HTML_NAMESPACE) {\n      // The only way to switch from SVG to HTML is via\n      // HTML integration points, and from MathML to HTML\n      // is via MathML text integration points\n      if (\n        parent.namespaceURI === SVG_NAMESPACE &&\n        !HTML_INTEGRATION_POINTS[parentTagName]\n      ) {\n        return false;\n      }\n\n      if (\n        parent.namespaceURI === MATHML_NAMESPACE &&\n        !MATHML_TEXT_INTEGRATION_POINTS[parentTagName]\n      ) {\n        return false;\n      }\n\n      // We disallow tags that are specific for MathML\n      // or SVG and should never appear in HTML namespace\n      return (\n        !ALL_MATHML_TAGS[tagName] &&\n        (COMMON_SVG_AND_HTML_ELEMENTS[tagName] || !ALL_SVG_TAGS[tagName])\n      );\n    }\n\n    // For XHTML and XML documents that support custom namespaces\n    if (\n      PARSER_MEDIA_TYPE === 'application/xhtml+xml' &&\n      ALLOWED_NAMESPACES[element.namespaceURI]\n    ) {\n      return true;\n    }\n\n    // The code should never reach this place (this means\n    // that the element somehow got namespace that is not\n    // HTML, SVG, MathML or allowed via ALLOWED_NAMESPACES).\n    // Return false just in case.\n    return false;\n  };\n\n  /**\n   * _forceRemove\n   *\n   * @param  {Node} node a DOM node\n   */\n  const _forceRemove = function (node) {\n    arrayPush(DOMPurify.removed, { element: node });\n    try {\n      // eslint-disable-next-line unicorn/prefer-dom-node-remove\n      node.parentNode.removeChild(node);\n    } catch (_) {\n      node.remove();\n    }\n  };\n\n  /**\n   * _removeAttribute\n   *\n   * @param  {String} name an Attribute name\n   * @param  {Node} node a DOM node\n   */\n  const _removeAttribute = function (name, node) {\n    try {\n      arrayPush(DOMPurify.removed, {\n        attribute: node.getAttributeNode(name),\n        from: node,\n      });\n    } catch (_) {\n      arrayPush(DOMPurify.removed, {\n        attribute: null,\n        from: node,\n      });\n    }\n\n    node.removeAttribute(name);\n\n    // We void attribute values for unremovable \"is\"\" attributes\n    if (name === 'is' && !ALLOWED_ATTR[name]) {\n      if (RETURN_DOM || RETURN_DOM_FRAGMENT) {\n        try {\n          _forceRemove(node);\n        } catch (_) {}\n      } else {\n        try {\n          node.setAttribute(name, '');\n        } catch (_) {}\n      }\n    }\n  };\n\n  /**\n   * _initDocument\n   *\n   * @param  {String} dirty a string of dirty markup\n   * @return {Document} a DOM, filled with the dirty markup\n   */\n  const _initDocument = function (dirty) {\n    /* Create a HTML document */\n    let doc;\n    let leadingWhitespace;\n\n    if (FORCE_BODY) {\n      dirty = '<remove></remove>' + dirty;\n    } else {\n      /* If FORCE_BODY isn't used, leading whitespace needs to be preserved manually */\n      const matches = stringMatch(dirty, /^[\\r\\n\\t ]+/);\n      leadingWhitespace = matches && matches[0];\n    }\n\n    if (\n      PARSER_MEDIA_TYPE === 'application/xhtml+xml' &&\n      NAMESPACE === HTML_NAMESPACE\n    ) {\n      // Root of XHTML doc must contain xmlns declaration (see https://www.w3.org/TR/xhtml1/normative.html#strict)\n      dirty =\n        '<html xmlns=\"http://www.w3.org/1999/xhtml\"><head></head><body>' +\n        dirty +\n        '</body></html>';\n    }\n\n    const dirtyPayload = trustedTypesPolicy\n      ? trustedTypesPolicy.createHTML(dirty)\n      : dirty;\n    /*\n     * Use the DOMParser API by default, fallback later if needs be\n     * DOMParser not work for svg when has multiple root element.\n     */\n    if (NAMESPACE === HTML_NAMESPACE) {\n      try {\n        doc = new DOMParser().parseFromString(dirtyPayload, PARSER_MEDIA_TYPE);\n      } catch (_) {}\n    }\n\n    /* Use createHTMLDocument in case DOMParser is not available */\n    if (!doc || !doc.documentElement) {\n      doc = implementation.createDocument(NAMESPACE, 'template', null);\n      try {\n        doc.documentElement.innerHTML = IS_EMPTY_INPUT\n          ? emptyHTML\n          : dirtyPayload;\n      } catch (_) {\n        // Syntax error if dirtyPayload is invalid xml\n      }\n    }\n\n    const body = doc.body || doc.documentElement;\n\n    if (dirty && leadingWhitespace) {\n      body.insertBefore(\n        document.createTextNode(leadingWhitespace),\n        body.childNodes[0] || null\n      );\n    }\n\n    /* Work on whole document or just its body */\n    if (NAMESPACE === HTML_NAMESPACE) {\n      return getElementsByTagName.call(\n        doc,\n        WHOLE_DOCUMENT ? 'html' : 'body'\n      )[0];\n    }\n\n    return WHOLE_DOCUMENT ? doc.documentElement : body;\n  };\n\n  /**\n   * _createIterator\n   *\n   * @param  {Document} root document/fragment to create iterator for\n   * @return {Iterator} iterator instance\n   */\n  const _createIterator = function (root) {\n    return createNodeIterator.call(\n      root.ownerDocument || root,\n      root,\n      // eslint-disable-next-line no-bitwise\n      NodeFilter.SHOW_ELEMENT | NodeFilter.SHOW_COMMENT | NodeFilter.SHOW_TEXT,\n      null,\n      false\n    );\n  };\n\n  /**\n   * _isClobbered\n   *\n   * @param  {Node} elm element to check for clobbering attacks\n   * @return {Boolean} true if clobbered, false if safe\n   */\n  const _isClobbered = function (elm) {\n    return (\n      elm instanceof HTMLFormElement &&\n      (typeof elm.nodeName !== 'string' ||\n        typeof elm.textContent !== 'string' ||\n        typeof elm.removeChild !== 'function' ||\n        !(elm.attributes instanceof NamedNodeMap) ||\n        typeof elm.removeAttribute !== 'function' ||\n        typeof elm.setAttribute !== 'function' ||\n        typeof elm.namespaceURI !== 'string' ||\n        typeof elm.insertBefore !== 'function' ||\n        typeof elm.hasChildNodes !== 'function')\n    );\n  };\n\n  /**\n   * _isNode\n   *\n   * @param  {Node} obj object to check whether it's a DOM node\n   * @return {Boolean} true is object is a DOM node\n   */\n  const _isNode = function (object) {\n    return typeof Node === 'object'\n      ? object instanceof Node\n      : object &&\n          typeof object === 'object' &&\n          typeof object.nodeType === 'number' &&\n          typeof object.nodeName === 'string';\n  };\n\n  /**\n   * _executeHook\n   * Execute user configurable hooks\n   *\n   * @param  {String} entryPoint  Name of the hook's entry point\n   * @param  {Node} currentNode node to work on with the hook\n   * @param  {Object} data additional hook parameters\n   */\n  const _executeHook = function (entryPoint, currentNode, data) {\n    if (!hooks[entryPoint]) {\n      return;\n    }\n\n    arrayForEach(hooks[entryPoint], (hook) => {\n      hook.call(DOMPurify, currentNode, data, CONFIG);\n    });\n  };\n\n  /**\n   * _sanitizeElements\n   *\n   * @protect nodeName\n   * @protect textContent\n   * @protect removeChild\n   *\n   * @param   {Node} currentNode to check for permission to exist\n   * @return  {Boolean} true if node was killed, false if left alive\n   */\n  const _sanitizeElements = function (currentNode) {\n    let content;\n\n    /* Execute a hook if present */\n    _executeHook('beforeSanitizeElements', currentNode, null);\n\n    /* Check if element is clobbered or can clobber */\n    if (_isClobbered(currentNode)) {\n      _forceRemove(currentNode);\n      return true;\n    }\n\n    /* Now let's check the element's type and name */\n    const tagName = transformCaseFunc(currentNode.nodeName);\n\n    /* Execute a hook if present */\n    _executeHook('uponSanitizeElement', currentNode, {\n      tagName,\n      allowedTags: ALLOWED_TAGS,\n    });\n\n    /* Detect mXSS attempts abusing namespace confusion */\n    if (\n      currentNode.hasChildNodes() &&\n      !_isNode(currentNode.firstElementChild) &&\n      (!_isNode(currentNode.content) ||\n        !_isNode(currentNode.content.firstElementChild)) &&\n      regExpTest(/<[/\\w]/g, currentNode.innerHTML) &&\n      regExpTest(/<[/\\w]/g, currentNode.textContent)\n    ) {\n      _forceRemove(currentNode);\n      return true;\n    }\n\n    /* Remove element if anything forbids its presence */\n    if (!ALLOWED_TAGS[tagName] || FORBID_TAGS[tagName]) {\n      /* Check if we have a custom element to handle */\n      if (!FORBID_TAGS[tagName] && _basicCustomElementTest(tagName)) {\n        if (\n          CUSTOM_ELEMENT_HANDLING.tagNameCheck instanceof RegExp &&\n          regExpTest(CUSTOM_ELEMENT_HANDLING.tagNameCheck, tagName)\n        )\n          return false;\n        if (\n          CUSTOM_ELEMENT_HANDLING.tagNameCheck instanceof Function &&\n          CUSTOM_ELEMENT_HANDLING.tagNameCheck(tagName)\n        )\n          return false;\n      }\n\n      /* Keep content except for bad-listed elements */\n      if (KEEP_CONTENT && !FORBID_CONTENTS[tagName]) {\n        const parentNode = getParentNode(currentNode) || currentNode.parentNode;\n        const childNodes = getChildNodes(currentNode) || currentNode.childNodes;\n\n        if (childNodes && parentNode) {\n          const childCount = childNodes.length;\n\n          for (let i = childCount - 1; i >= 0; --i) {\n            parentNode.insertBefore(\n              cloneNode(childNodes[i], true),\n              getNextSibling(currentNode)\n            );\n          }\n        }\n      }\n\n      _forceRemove(currentNode);\n      return true;\n    }\n\n    /* Check whether element has a valid namespace */\n    if (currentNode instanceof Element && !_checkValidNamespace(currentNode)) {\n      _forceRemove(currentNode);\n      return true;\n    }\n\n    /* Make sure that older browsers don't get fallback-tag mXSS */\n    if (\n      (tagName === 'noscript' ||\n        tagName === 'noembed' ||\n        tagName === 'noframes') &&\n      regExpTest(/<\\/no(script|embed|frames)/i, currentNode.innerHTML)\n    ) {\n      _forceRemove(currentNode);\n      return true;\n    }\n\n    /* Sanitize element content to be template-safe */\n    if (SAFE_FOR_TEMPLATES && currentNode.nodeType === 3) {\n      /* Get the element's text content */\n      content = currentNode.textContent;\n      content = stringReplace(content, MUSTACHE_EXPR, ' ');\n      content = stringReplace(content, ERB_EXPR, ' ');\n      content = stringReplace(content, TMPLIT_EXPR, ' ');\n      if (currentNode.textContent !== content) {\n        arrayPush(DOMPurify.removed, { element: currentNode.cloneNode() });\n        currentNode.textContent = content;\n      }\n    }\n\n    /* Execute a hook if present */\n    _executeHook('afterSanitizeElements', currentNode, null);\n\n    return false;\n  };\n\n  /**\n   * _isValidAttribute\n   *\n   * @param  {string} lcTag Lowercase tag name of containing element.\n   * @param  {string} lcName Lowercase attribute name.\n   * @param  {string} value Attribute value.\n   * @return {Boolean} Returns true if `value` is valid, otherwise false.\n   */\n  // eslint-disable-next-line complexity\n  const _isValidAttribute = function (lcTag, lcName, value) {\n    /* Make sure attribute cannot clobber */\n    if (\n      SANITIZE_DOM &&\n      (lcName === 'id' || lcName === 'name') &&\n      (value in document || value in formElement)\n    ) {\n      return false;\n    }\n\n    /* Allow valid data-* attributes: At least one character after \"-\"\n        (https://html.spec.whatwg.org/multipage/dom.html#embedding-custom-non-visible-data-with-the-data-*-attributes)\n        XML-compatible (https://html.spec.whatwg.org/multipage/infrastructure.html#xml-compatible and http://www.w3.org/TR/xml/#d0e804)\n        We don't need to check the value; it's always URI safe. */\n    if (\n      ALLOW_DATA_ATTR &&\n      !FORBID_ATTR[lcName] &&\n      regExpTest(DATA_ATTR, lcName)\n    ) {\n      // This attribute is safe\n    } else if (ALLOW_ARIA_ATTR && regExpTest(ARIA_ATTR, lcName)) {\n      // This attribute is safe\n      /* Otherwise, check the name is permitted */\n    } else if (!ALLOWED_ATTR[lcName] || FORBID_ATTR[lcName]) {\n      if (\n        // First condition does a very basic check if a) it's basically a valid custom element tagname AND\n        // b) if the tagName passes whatever the user has configured for CUSTOM_ELEMENT_HANDLING.tagNameCheck\n        // and c) if the attribute name passes whatever the user has configured for CUSTOM_ELEMENT_HANDLING.attributeNameCheck\n        (_basicCustomElementTest(lcTag) &&\n          ((CUSTOM_ELEMENT_HANDLING.tagNameCheck instanceof RegExp &&\n            regExpTest(CUSTOM_ELEMENT_HANDLING.tagNameCheck, lcTag)) ||\n            (CUSTOM_ELEMENT_HANDLING.tagNameCheck instanceof Function &&\n              CUSTOM_ELEMENT_HANDLING.tagNameCheck(lcTag))) &&\n          ((CUSTOM_ELEMENT_HANDLING.attributeNameCheck instanceof RegExp &&\n            regExpTest(CUSTOM_ELEMENT_HANDLING.attributeNameCheck, lcName)) ||\n            (CUSTOM_ELEMENT_HANDLING.attributeNameCheck instanceof Function &&\n              CUSTOM_ELEMENT_HANDLING.attributeNameCheck(lcName)))) ||\n        // Alternative, second condition checks if it's an `is`-attribute, AND\n        // the value passes whatever the user has configured for CUSTOM_ELEMENT_HANDLING.tagNameCheck\n        (lcName === 'is' &&\n          CUSTOM_ELEMENT_HANDLING.allowCustomizedBuiltInElements &&\n          ((CUSTOM_ELEMENT_HANDLING.tagNameCheck instanceof RegExp &&\n            regExpTest(CUSTOM_ELEMENT_HANDLING.tagNameCheck, value)) ||\n            (CUSTOM_ELEMENT_HANDLING.tagNameCheck instanceof Function &&\n              CUSTOM_ELEMENT_HANDLING.tagNameCheck(value))))\n      ) {\n        // If user has supplied a regexp or function in CUSTOM_ELEMENT_HANDLING.tagNameCheck, we need to also allow derived custom elements using the same tagName test.\n        // Additionally, we need to allow attributes passing the CUSTOM_ELEMENT_HANDLING.attributeNameCheck user has configured, as custom elements can define these at their own discretion.\n      } else {\n        return false;\n      }\n      /* Check value is safe. First, is attr inert? If so, is safe */\n    } else if (URI_SAFE_ATTRIBUTES[lcName]) {\n      // This attribute is safe\n      /* Check no script, data or unknown possibly unsafe URI\n        unless we know URI values are safe for that attribute */\n    } else if (\n      regExpTest(IS_ALLOWED_URI, stringReplace(value, ATTR_WHITESPACE, ''))\n    ) {\n      // This attribute is safe\n      /* Keep image data URIs alive if src/xlink:href is allowed */\n      /* Further prevent gadget XSS for dynamically built script tags */\n    } else if (\n      (lcName === 'src' || lcName === 'xlink:href' || lcName === 'href') &&\n      lcTag !== 'script' &&\n      stringIndexOf(value, 'data:') === 0 &&\n      DATA_URI_TAGS[lcTag]\n    ) {\n      // This attribute is safe\n      /* Allow unknown protocols: This provides support for links that\n        are handled by protocol handlers which may be unknown ahead of\n        time, e.g. fb:, spotify: */\n    } else if (\n      ALLOW_UNKNOWN_PROTOCOLS &&\n      !regExpTest(IS_SCRIPT_OR_DATA, stringReplace(value, ATTR_WHITESPACE, ''))\n    ) {\n      // This attribute is safe\n      /* Check for binary attributes */\n    } else if (value) {\n      return false;\n    } else {\n      // Binary attributes are safe at this point\n      /* Anything else, presume unsafe, do not add it back */