diff --git a/Meta/gn/secondary/Userland/Libraries/LibWeb/CSS/BUILD.gn b/Meta/gn/secondary/Userland/Libraries/LibWeb/CSS/BUILD.gn
index 0a8a368714dbe0..c9b626e357d10f 100644
--- a/Meta/gn/secondary/Userland/Libraries/LibWeb/CSS/BUILD.gn
+++ b/Meta/gn/secondary/Userland/Libraries/LibWeb/CSS/BUILD.gn
@@ -67,6 +67,7 @@ source_set("CSS") {
     "StyleProperties.cpp",
     "StyleProperty.cpp",
     "StyleSheet.cpp",
+    "StyleSheetIdentifier.cpp",
     "StyleSheetList.cpp",
     "Supports.cpp",
     "SystemColor.cpp",