diff --git a/inputfiles/addedTypes.jsonc b/inputfiles/addedTypes.jsonc
index 7fe2c8824..c7ccd5d4e 100644
--- a/inputfiles/addedTypes.jsonc
+++ b/inputfiles/addedTypes.jsonc
@@ -400,7 +400,6 @@
                 "name": "StyleMedia",
                 "exposed": "Window",
                 "noInterfaceObject": true,
-                "deprecated": true,
                 "properties": {
                     "property": {
                         "type": {
diff --git a/inputfiles/patches/cssom.kdl b/inputfiles/patches/cssom.kdl
index a3baf2c5c..fdb03b695 100644
--- a/inputfiles/patches/cssom.kdl
+++ b/inputfiles/patches/cssom.kdl
@@ -7,3 +7,5 @@ interface CSSStyleDeclaration \
   forwardExtends=CSSStyleProperties
 
 interface CSSStyleProperties replaceReference=CSSStyleDeclaration
+
+interface StyleMedia deprecated=#true
diff --git a/src/build/patches.ts b/src/build/patches.ts
index 6bf60fa05..3a31e0d95 100644
--- a/src/build/patches.ts
+++ b/src/build/patches.ts
@@ -15,12 +15,16 @@ type DeepPartial<T> = T extends object
   ? { [K in keyof T]?: DeepPartial<T[K]> }
   : T;
 
-function optionalMember<const T>(prop: string, type: T, value?: Value) {
+function optionalMember<const T>(prop: string, type: T | T[], value?: Value) {
   if (value === undefined) {
     return {};
   }
-  if (typeof value !== type) {
-    throw new Error(`Expected type ${value} for ${prop}`);
+  const types = Array.isArray(type) ? type : [type];
+  const valueType = typeof value;
+  if (!types.includes(valueType as T)) {
+    throw new Error(
+      `Expected type ${types.join(" or ")} for ${prop}, but got ${valueType}`,
+    );
   }
   return {
     [prop]: value as T extends "string"
@@ -169,7 +173,11 @@ function handleMixinandInterfaces(
 
   const interfaceObject = type === "interface" && {
     ...optionalMember("exposed", "string", node.properties?.exposed),
-    ...optionalMember("deprecated", "string", node.properties?.deprecated),
+    ...optionalMember(
+      "deprecated",
+      ["string", "boolean"],
+      node.properties?.deprecated,
+    ),
     ...optionalMember(
       "noInterfaceObject",
       "boolean",