fix: Made use of proper helper method to get parentNode

test: fixed several more MSIE11 tests

Author: cure53

dist/purify.cjs.js

@@ -507,7 +507,7 @@ function createDOMPurify(window = getGlobal()) {
    *  return. Return true otherwise.
    */
   const _checkValidNamespace = function (element) {
-    let parent = element.parentNode;
+    let parent = getParentNode(element);
 
     // In JSDOM, if we're inside shadow DOM, then parentNode
     // can be null. We just simulate parent in this case.

dist/purify.cjs.js.map

@@ -1022,7 +1022,7 @@ module.exports = [
           "<svg></svg><p></p><title>&lt;a id=\"</title><img src=\"x\">\"&gt;",
           "<svg><title><a id=\"</title><img src=x onerror=alert()>\"></a></title></svg>",
           "<svg xmlns=\"http://www.w3.org/2000/svg\"><title><a id=\"</title><img src=x onerror=alert()>\"></a></title></svg>",
-          "<svg xmlns=\"http://www.w3.org/2000/svg\" />"
+          "<svg xmlns=\"http://www.w3.org/2000/svg\"><title><a id=\"</title><img src=x onerror=alert()>\"></a></title></title></svg></svg>"
       ]
   }, {
       "title": "Tests against mXSS behavior with MathML in Chrome 77 and alike",
@@ -1042,7 +1042,7 @@ module.exports = [
           "<svg></svg><p></p><img src=\"x\">",
           "<svg><title><template></template></title></svg>",
           "<svg xmlns=\"http://www.w3.org/2000/svg\"><title><template></template></title></svg>",
-          "<svg xmlns=\"http://www.w3.org/2000/svg\" />"
+          "<svg xmlns=\"http://www.w3.org/2000/svg\"><title><template></template></title></title></svg></svg>"
       ]
   }, {
       "title": "Tests against mXSS behavior with MathML Templates in Chrome 77 and alike",