unvendor: Replace DOMPurify

public/lib.js

@@ -3,7 +3,33 @@
  * They are bundled and exposed by Webpack in the /lib.js file.
  */
 import Fuse from 'fuse.js';
+import DOMPurify from 'dompurify';
+
+/**
+ * Expose the libraries to the 'window' object.
+ * Needed for compatibility with old extensions.
+ * Note: New extensions are encouraged to import the libraries directly from lib.js.
+ */
+export function initLibraryShims() {
+    if (!window) {
+        return;
+    }
+    if (!('Fuse' in window)) {
+        // @ts-ignore
+        window.Fuse = Fuse;
+    }
+    if (!('DOMPurify' in window)) {
+        // @ts-ignore
+        window.DOMPurify = DOMPurify;
+    }
+}
+
+export default {
+    Fuse,
+    DOMPurify,
+};
 
 export {
     Fuse,
+    DOMPurify,
 };