diff --git a/baselines/dom.generated.d.ts b/baselines/dom.generated.d.ts
index b303baf18..056f4a02a 100644
--- a/baselines/dom.generated.d.ts
+++ b/baselines/dom.generated.d.ts
@@ -3450,6 +3450,7 @@ declare var Document: {
 }
 
 interface DocumentFragment extends Node, NodeSelector, ParentNode {
+    getElementById(elementId: string): HTMLElement | null;
 }
 
 declare var DocumentFragment: {
diff --git a/inputfiles/addedTypes.json b/inputfiles/addedTypes.json
index 5489332f8..a1d7f851d 100644
--- a/inputfiles/addedTypes.json
+++ b/inputfiles/addedTypes.json
@@ -1444,5 +1444,12 @@
         "name": "formData",
         "flavor": "Web",
         "signatures": ["formData(): Promise<FormData>"]
+    },
+    {
+        "kind": "method",
+        "interface": "DocumentFragment",
+        "name": "getElementById",
+        "flavor": "DOM",
+        "signatures": ["getElementById(elementId: string): HTMLElement | null"]
     }
 ]