diff --git a/components/script/dom/characterdata.rs b/components/script/dom/characterdata.rs
index ade189739c3..2d6bfbb706f 100644
--- a/components/script/dom/characterdata.rs
+++ b/components/script/dom/characterdata.rs
@@ -64,6 +64,7 @@ impl CharacterData {
 
     #[inline]
     pub fn append_data(&self, data: &str) {
+        self.queue_mutation_record();
         self.data.borrow_mut().push_str(data);
         self.content_changed();
     }
diff --git a/tests/wpt/metadata/dom/nodes/MutationObserver-characterData.html.ini b/tests/wpt/metadata/dom/nodes/MutationObserver-characterData.html.ini
deleted file mode 100644
index 9a4b39b2421..00000000000
--- a/tests/wpt/metadata/dom/nodes/MutationObserver-characterData.html.ini
+++ /dev/null
@@ -1,12 +0,0 @@
-[MutationObserver-characterData.html]
-  type: testharness
-  expected: TIMEOUT
-  [characterData Text.appendData: simple mutation]
-    expected: TIMEOUT
-
-  [characterData Text.appendData: empty string mutation]
-    expected: TIMEOUT
-
-  [characterData Text.appendData: null string mutation]
-    expected: TIMEOUT
-