Index: frontend/node_modules/w3c-xmlserializer/lib/attributes.js
===================================================================
--- frontend/node_modules/w3c-xmlserializer/lib/attributes.js	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
+++ frontend/node_modules/w3c-xmlserializer/lib/attributes.js	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
@@ -0,0 +1,128 @@
+"use strict";
+
+const xnv = require("xml-name-validator");
+
+const { NAMESPACES } = require("./constants");
+
+function generatePrefix(map, newNamespace, prefixIndex) {
+  const generatedPrefix = "ns" + prefixIndex;
+  map[newNamespace] = [generatedPrefix];
+  return generatedPrefix;
+}
+
+function preferredPrefixString(map, ns, preferredPrefix) {
+  const candidateList = map[ns];
+  if (!candidateList) {
+    return null;
+  }
+  if (candidateList.includes(preferredPrefix)) {
+    return preferredPrefix;
+  }
+  return candidateList[candidateList.length - 1];
+}
+
+function serializeAttributeValue(value/* , requireWellFormed*/) {
+  if (value === null) {
+    return "";
+  }
+  // TODO: Check well-formedness
+  return value
+    .replace(/&/g, "&")
+    .replace(/"/g, """)
+    .replace(/</g, "&lt;")
+    .replace(/>/g, "&gt;")
+    .replace(/\t/g, "&#x9;")
+    .replace(/\n/g, "&#xA;")
+    .replace(/\r/g, "&#xD;");
+}
+
+function serializeAttributes(
+  element,
+  map,
+  localPrefixes,
+  ignoreNamespaceDefAttr,
+  requireWellFormed,
+  refs
+) {
+  let result = "";
+  const namespaceLocalnames = Object.create(null);
+  for (const attr of element.attributes) {
+    if (
+      requireWellFormed &&
+      namespaceLocalnames[attr.namespaceURI] &&
+      namespaceLocalnames[attr.namespaceURI].has(attr.localName)
+    ) {
+      throw new Error("Found duplicated attribute");
+    }
+    if (!namespaceLocalnames[attr.namespaceURI]) {
+      namespaceLocalnames[attr.namespaceURI] = new Set();
+    }
+    namespaceLocalnames[attr.namespaceURI].add(attr.localName);
+    const attributeNamespace = attr.namespaceURI;
+    let candidatePrefix = null;
+    if (attributeNamespace !== null) {
+      candidatePrefix = preferredPrefixString(
+        map,
+        attributeNamespace,
+        attr.prefix
+      );
+      if (attributeNamespace === NAMESPACES.XMLNS) {
+        if (
+          attr.value === NAMESPACES.XML ||
+          (attr.prefix === null && ignoreNamespaceDefAttr) ||
+          (attr.prefix !== null &&
+            localPrefixes[attr.localName] !== attr.value &&
+            map[attr.value].includes(attr.localName))
+        ) {
+          continue;
+        }
+        if (requireWellFormed && attr.value === NAMESPACES.XMLNS) {
+          throw new Error(
+            "The XMLNS namespace is reserved and cannot be applied as an element's namespace via XML parsing"
+          );
+        }
+        if (requireWellFormed && attr.value === "") {
+          throw new Error(
+            "Namespace prefix declarations cannot be used to undeclare a namespace"
+          );
+        }
+        if (attr.prefix === "xmlns") {
+          candidatePrefix = "xmlns";
+        }
+      } else if (candidatePrefix === null) {
+        candidatePrefix = generatePrefix(
+          map,
+          attributeNamespace,
+          refs.prefixIndex++
+        );
+        result += ` xmlns:${candidatePrefix}="${serializeAttributeValue(
+          attributeNamespace,
+          requireWellFormed
+        )}"`;
+      }
+    }
+
+    result += " ";
+    if (candidatePrefix !== null) {
+      result += candidatePrefix + ":";
+    }
+    if (
+      requireWellFormed &&
+      (attr.localName.includes(":") ||
+        !xnv.name(attr.localName) ||
+        (attr.localName === "xmlns" && attributeNamespace === null))
+    ) {
+      throw new Error("Invalid attribute localName value");
+    }
+    result += `${attr.localName}="${serializeAttributeValue(
+      attr.value,
+      requireWellFormed
+    )}"`;
+  }
+  return result;
+}
+
+module.exports.preferredPrefixString = preferredPrefixString;
+module.exports.generatePrefix = generatePrefix;
+module.exports.serializeAttributeValue = serializeAttributeValue;
+module.exports.serializeAttributes = serializeAttributes;
Index: frontend/node_modules/w3c-xmlserializer/lib/constants.js
===================================================================
--- frontend/node_modules/w3c-xmlserializer/lib/constants.js	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
+++ frontend/node_modules/w3c-xmlserializer/lib/constants.js	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
@@ -0,0 +1,44 @@
+"use strict";
+
+module.exports.NAMESPACES = {
+  HTML: "http://www.w3.org/1999/xhtml",
+  XML: "http://www.w3.org/XML/1998/namespace",
+  XMLNS: "http://www.w3.org/2000/xmlns/"
+};
+
+module.exports.NODE_TYPES = {
+  ELEMENT_NODE: 1,
+  ATTRIBUTE_NODE: 2, // historical
+  TEXT_NODE: 3,
+  CDATA_SECTION_NODE: 4,
+  ENTITY_REFERENCE_NODE: 5, // historical
+  ENTITY_NODE: 6, // historical
+  PROCESSING_INSTRUCTION_NODE: 7,
+  COMMENT_NODE: 8,
+  DOCUMENT_NODE: 9,
+  DOCUMENT_TYPE_NODE: 10,
+  DOCUMENT_FRAGMENT_NODE: 11,
+  NOTATION_NODE: 12 // historical
+};
+
+module.exports.VOID_ELEMENTS = new Set([
+  "area",
+  "base",
+  "basefont",
+  "bgsound",
+  "br",
+  "col",
+  "embed",
+  "frame",
+  "hr",
+  "img",
+  "input",
+  "keygen",
+  "link",
+  "menuitem",
+  "meta",
+  "param",
+  "source",
+  "track",
+  "wbr"
+]);
Index: frontend/node_modules/w3c-xmlserializer/lib/serialize.js
===================================================================
--- frontend/node_modules/w3c-xmlserializer/lib/serialize.js	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
+++ frontend/node_modules/w3c-xmlserializer/lib/serialize.js	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
@@ -0,0 +1,371 @@
+"use strict";
+
+const xnv = require("xml-name-validator");
+
+const attributeUtils = require("./attributes");
+const { NAMESPACES, VOID_ELEMENTS, NODE_TYPES } = require("./constants");
+
+const XML_CHAR = /^(\x09|\x0A|\x0D|[\x20-\uD7FF]|[\uE000-\uFFFD]|(?:[\uD800-\uDBFF][\uDC00-\uDFFF]))*$/;
+const PUBID_CHAR = /^(\x20|\x0D|\x0A|[a-zA-Z0-9]|[-'()+,./:=?;!*#@$_%])*$/;
+
+function asciiCaseInsensitiveMatch(a, b) {
+  if (a.length !== b.length) {
+    return false;
+  }
+
+  for (let i = 0; i < a.length; ++i) {
+    if ((a.charCodeAt(i) | 32) !== (b.charCodeAt(i) | 32)) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+function recordNamespaceInformation(element, map, prefixMap) {
+  let defaultNamespaceAttrValue = null;
+  for (let i = 0; i < element.attributes.length; ++i) {
+    const attr = element.attributes[i];
+    if (attr.namespaceURI === NAMESPACES.XMLNS) {
+      if (attr.prefix === null) {
+        defaultNamespaceAttrValue = attr.value;
+        continue;
+      }
+      let namespaceDefinition = attr.value;
+      if (namespaceDefinition === NAMESPACES.XML) {
+        continue;
+      }
+      // This is exactly the other way than the spec says, but that's intended.
+      // All the maps coalesce null to the empty string (explained in the
+      // spec), so instead of doing that every time, just do it once here.
+      if (namespaceDefinition === null) {
+        namespaceDefinition = "";
+      }
+
+      if (
+        namespaceDefinition in map &&
+        map[namespaceDefinition].includes(attr.localName)
+      ) {
+        continue;
+      }
+      if (!(namespaceDefinition in map)) {
+        map[namespaceDefinition] = [];
+      }
+      map[namespaceDefinition].push(attr.localName);
+      prefixMap[attr.localName] = namespaceDefinition;
+    }
+  }
+  return defaultNamespaceAttrValue;
+}
+
+function serializeDocumentType(node, namespace, prefixMap, requireWellFormed) {
+  if (requireWellFormed && !PUBID_CHAR.test(node.publicId)) {
+    throw new Error("Failed to serialize XML: document type node publicId is not well-formed.");
+  }
+
+  if (
+    requireWellFormed &&
+    (!XML_CHAR.test(node.systemId) ||
+      (node.systemId.includes('"') && node.systemId.includes("'")))
+  ) {
+    throw new Error("Failed to serialize XML: document type node systemId is not well-formed.");
+  }
+
+  let markup = `<!DOCTYPE ${node.name}`;
+  if (node.publicId !== "") {
+    markup += ` PUBLIC "${node.publicId}"`;
+  } else if (node.systemId !== "") {
+    markup += " SYSTEM";
+  }
+  if (node.systemId !== "") {
+    markup += ` "${node.systemId}"`;
+  }
+  return markup + ">";
+}
+
+function serializeProcessingInstruction(
+  node,
+  namespace,
+  prefixMap,
+  requireWellFormed
+) {
+  if (
+    requireWellFormed &&
+    (node.target.includes(":") || asciiCaseInsensitiveMatch(node.target, "xml"))
+  ) {
+    throw new Error("Failed to serialize XML: processing instruction node target is not well-formed.");
+  }
+  if (
+    requireWellFormed &&
+    (!XML_CHAR.test(node.data) || node.data.includes("?>"))
+  ) {
+    throw new Error("Failed to serialize XML: processing instruction node data is not well-formed.");
+  }
+  return `<?${node.target} ${node.data}?>`;
+}
+
+function serializeDocument(
+  node,
+  namespace,
+  prefixMap,
+  requireWellFormed,
+  refs
+) {
+  if (requireWellFormed && node.documentElement === null) {
+    throw new Error("Failed to serialize XML: document does not have a document element.");
+  }
+  let serializedDocument = "";
+  for (const child of node.childNodes) {
+    serializedDocument += xmlSerialization(
+      child,
+      namespace,
+      prefixMap,
+      requireWellFormed,
+      refs
+    );
+  }
+  return serializedDocument;
+}
+
+function serializeDocumentFragment(
+  node,
+  namespace,
+  prefixMap,
+  requireWellFormed,
+  refs
+) {
+  let markup = "";
+  for (const child of node.childNodes) {
+    markup += xmlSerialization(
+      child,
+      namespace,
+      prefixMap,
+      requireWellFormed,
+      refs
+    );
+  }
+  return markup;
+}
+
+function serializeText(node, namespace, prefixMap, requireWellFormed) {
+  if (requireWellFormed && !XML_CHAR.test(node.data)) {
+    throw new Error("Failed to serialize XML: text node data is not well-formed.");
+  }
+
+  return node.data
+    .replace(/&/g, "&amp;")
+    .replace(/</g, "&lt;")
+    .replace(/>/g, "&gt;");
+}
+
+function serializeComment(node, namespace, prefixMap, requireWellFormed) {
+  if (requireWellFormed && !XML_CHAR.test(node.data)) {
+    throw new Error("Failed to serialize XML: comment node data is not well-formed.");
+  }
+
+  if (
+    requireWellFormed &&
+    (node.data.includes("--") || node.data.endsWith("-"))
+  ) {
+    throw new Error("Failed to serialize XML: found hyphens in illegal places in comment node data.");
+  }
+  return `<!--${node.data}-->`;
+}
+
+function serializeElement(node, namespace, prefixMap, requireWellFormed, refs) {
+  if (
+    requireWellFormed &&
+    (node.localName.includes(":") || !xnv.name(node.localName))
+  ) {
+    throw new Error("Failed to serialize XML: element node localName is not a valid XML name.");
+  }
+  let markup = "<";
+  let qualifiedName = "";
+  let skipEndTag = false;
+  let ignoreNamespaceDefinitionAttr = false;
+  const map = Object.assign({}, prefixMap);
+  const localPrefixesMap = Object.create(null);
+  const localDefaultNamespace = recordNamespaceInformation(
+    node,
+    map,
+    localPrefixesMap
+  );
+  let inheritedNs = namespace;
+  const ns = node.namespaceURI;
+  if (inheritedNs === ns) {
+    if (localDefaultNamespace !== null) {
+      ignoreNamespaceDefinitionAttr = true;
+    }
+    if (ns === NAMESPACES.XML) {
+      qualifiedName = "xml:" + node.localName;
+    } else {
+      qualifiedName = node.localName;
+    }
+    markup += qualifiedName;
+  } else {
+    let { prefix } = node;
+    let candidatePrefix = attributeUtils.preferredPrefixString(map, ns, prefix);
+    if (prefix === "xmlns") {
+      if (requireWellFormed) {
+        throw new Error("Failed to serialize XML: element nodes can't have a prefix of \"xmlns\".");
+      }
+      candidatePrefix = "xmlns";
+    }
+    if (candidatePrefix !== null) {
+      qualifiedName = candidatePrefix + ":" + node.localName;
+      if (
+        localDefaultNamespace !== null &&
+        localDefaultNamespace !== NAMESPACES.XML
+      ) {
+        inheritedNs =
+          localDefaultNamespace === "" ? null : localDefaultNamespace;
+      }
+      markup += qualifiedName;
+    } else if (prefix !== null) {
+      if (prefix in localPrefixesMap) {
+        prefix = attributeUtils.generatePrefix(map, ns, refs.prefixIndex++);
+      }
+      if (map[ns]) {
+        map[ns].push(prefix);
+      } else {
+        map[ns] = [prefix];
+      }
+      qualifiedName = prefix + ":" + node.localName;
+      markup += `${qualifiedName} xmlns:${prefix}="${attributeUtils.serializeAttributeValue(
+        ns,
+        requireWellFormed
+      )}"`;
+      if (localDefaultNamespace !== null) {
+        inheritedNs =
+          localDefaultNamespace === "" ? null : localDefaultNamespace;
+      }
+    } else if (localDefaultNamespace === null || localDefaultNamespace !== ns) {
+      ignoreNamespaceDefinitionAttr = true;
+      qualifiedName = node.localName;
+      inheritedNs = ns;
+      markup += `${qualifiedName} xmlns="${attributeUtils.serializeAttributeValue(
+        ns,
+        requireWellFormed
+      )}"`;
+    } else {
+      qualifiedName = node.localName;
+      inheritedNs = ns;
+      markup += qualifiedName;
+    }
+  }
+
+  markup += attributeUtils.serializeAttributes(
+    node,
+    map,
+    localPrefixesMap,
+    ignoreNamespaceDefinitionAttr,
+    requireWellFormed,
+    refs
+  );
+
+  if (
+    ns === NAMESPACES.HTML &&
+    node.childNodes.length === 0 &&
+    VOID_ELEMENTS.has(node.localName)
+  ) {
+    markup += " /";
+    skipEndTag = true;
+  } else if (ns !== NAMESPACES.HTML && node.childNodes.length === 0) {
+    markup += "/";
+    skipEndTag = true;
+  }
+  markup += ">";
+  if (skipEndTag) {
+    return markup;
+  }
+
+  if (ns === NAMESPACES.HTML && node.localName === "template") {
+    markup += xmlSerialization(
+      node.content,
+      inheritedNs,
+      map,
+      requireWellFormed,
+      refs
+    );
+  } else {
+    for (const child of node.childNodes) {
+      markup += xmlSerialization(
+        child,
+        inheritedNs,
+        map,
+        requireWellFormed,
+        refs
+      );
+    }
+  }
+  markup += `</${qualifiedName}>`;
+  return markup;
+}
+
+function serializeCDATASection(node) {
+  return "<![CDATA[" + node.data + "]]>";
+}
+
+/**
+ * @param {{prefixIndex: number}} refs
+ */
+function xmlSerialization(node, namespace, prefixMap, requireWellFormed, refs) {
+  switch (node.nodeType) {
+    case NODE_TYPES.ELEMENT_NODE:
+      return serializeElement(
+        node,
+        namespace,
+        prefixMap,
+        requireWellFormed,
+        refs
+      );
+    case NODE_TYPES.DOCUMENT_NODE:
+      return serializeDocument(
+        node,
+        namespace,
+        prefixMap,
+        requireWellFormed,
+        refs
+      );
+    case NODE_TYPES.COMMENT_NODE:
+      return serializeComment(node, namespace, prefixMap, requireWellFormed);
+    case NODE_TYPES.TEXT_NODE:
+      return serializeText(node, namespace, prefixMap, requireWellFormed);
+    case NODE_TYPES.DOCUMENT_FRAGMENT_NODE:
+      return serializeDocumentFragment(
+        node,
+        namespace,
+        prefixMap,
+        requireWellFormed,
+        refs
+      );
+    case NODE_TYPES.DOCUMENT_TYPE_NODE:
+      return serializeDocumentType(
+        node,
+        namespace,
+        prefixMap,
+        requireWellFormed
+      );
+    case NODE_TYPES.PROCESSING_INSTRUCTION_NODE:
+      return serializeProcessingInstruction(
+        node,
+        namespace,
+        prefixMap,
+        requireWellFormed
+      );
+    case NODE_TYPES.ATTRIBUTE_NODE:
+      return "";
+    case NODE_TYPES.CDATA_SECTION_NODE:
+      return serializeCDATASection(node);
+    default:
+      throw new TypeError("Failed to serialize XML: only Nodes can be serialized.");
+  }
+}
+
+module.exports = (root, { requireWellFormed = false } = {}) => {
+  const namespacePrefixMap = Object.create(null);
+  namespacePrefixMap["http://www.w3.org/XML/1998/namespace"] = ["xml"];
+  return xmlSerialization(root, null, namespacePrefixMap, requireWellFormed, {
+    prefixIndex: 1
+  });
+};