diff --git a/package.json b/package.json
index 9612052..c5700b3 100644
--- a/package.json
+++ b/package.json
@@ -86,7 +86,10 @@
       "^react$": "preact/compat",
       "^react-dom/test-utils$": "preact/test-utils",
       "^react-dom$": "preact/compat"
-    }
+    },
+    "setupFilesAfterEnv": [
+      "<rootDir>/spec/setupTests.js"
+    ]
   },
   "snapshotSerializers": [
     "preact-render-spy/snapshot"
diff --git a/spec/setupTests.js b/spec/setupTests.js
new file mode 100644
index 0000000..2edf6b0
--- /dev/null
+++ b/spec/setupTests.js
@@ -0,0 +1,7 @@
+// Work-around for jsdom not supporting offsetParent
+// https://github.com/jsdom/jsdom/issues/1261
+Object.defineProperty(HTMLElement.prototype, 'offsetParent', {
+  get() {
+    return this.parentNode;
+  },
+});
diff --git a/src/components/JustNotSorry.js b/src/components/JustNotSorry.js
index ecd87cf..3f2af02 100644
--- a/src/components/JustNotSorry.js
+++ b/src/components/JustNotSorry.js
@@ -50,8 +50,8 @@ class JustNotSorry extends Component {
         : findRanges(email, patterns);
 
     this.setState(({ parentNode }) =>
-      parentNode.id !== email.parentNode.id
-        ? { parentNode: email.parentNode, warnings: newWarnings }
+      parentNode.id !== email.offsetParent.id
+        ? { parentNode: email.offsetParent, warnings: newWarnings }
         : { parentNode, warnings: newWarnings }
     );
   }