diff --git a/extensions/theme-defaults/themes/dark_vs.json b/extensions/theme-defaults/themes/dark_vs.json
index fe0f8fc889c..479b5fd8988 100644
--- a/extensions/theme-defaults/themes/dark_vs.json
+++ b/extensions/theme-defaults/themes/dark_vs.json
@@ -306,6 +306,7 @@
 				"keyword.operator.expression",
 				"keyword.operator.cast",
 				"keyword.operator.sizeof",
+				"keyword.operator.alignof",
 				"keyword.operator.typeid",
 				"keyword.operator.alignas",
 				"keyword.operator.instanceof",
diff --git a/extensions/theme-defaults/themes/light_vs.json b/extensions/theme-defaults/themes/light_vs.json
index 74bd28d2455..886d1175c8b 100644
--- a/extensions/theme-defaults/themes/light_vs.json
+++ b/extensions/theme-defaults/themes/light_vs.json
@@ -330,6 +330,7 @@
 				"keyword.operator.expression",
 				"keyword.operator.cast",
 				"keyword.operator.sizeof",
+				"keyword.operator.alignof",
 				"keyword.operator.typeid",
 				"keyword.operator.alignas",
 				"keyword.operator.instanceof",