diff --git a/build/index.ts b/build/index.ts
index cd165e4a7228..b251679c3308 100644
--- a/build/index.ts
+++ b/build/index.ts
@@ -217,9 +217,13 @@ export async function buildDocument(
   let flaws: any[] = [];
   let $: cheerio.CheerioAPI = null;
   const liveSamples: LiveSample[] = [];
+  // this will get populated with the parent's frontmatter by kumascript if the document is localized:
+  let allMetadata = metadata;
 
   try {
-    [$, flaws] = await kumascript.render(document.url);
+    let kumascriptMetadata;
+    [$, flaws, kumascriptMetadata] = await kumascript.render(document.url);
+    allMetadata = { ...allMetadata, ...kumascriptMetadata };
   } catch (error) {
     if (
       error instanceof MacroInvocationError &&
@@ -369,7 +373,9 @@ export async function buildDocument(
   doc.mdn_url = document.url;
   doc.locale = metadata.locale as string;
   doc.native = LANGUAGES.get(doc.locale.toLowerCase())?.native;
-  const browserCompat = metadata["browser-compat"];
+
+  // metadata doesn't have a browser-compat key on translated docs:
+  const browserCompat = allMetadata["browser-compat"];
   doc.browserCompat =
     browserCompat &&
     (Array.isArray(browserCompat) ? browserCompat : [browserCompat]);
diff --git a/kumascript/index.ts b/kumascript/index.ts
index 9e6cbb7c6a63..51f1a0b09716 100644
--- a/kumascript/index.ts
+++ b/kumascript/index.ts
@@ -38,14 +38,14 @@ export async function render(
     invalidateCache = false,
   }: RenderOptions = {},
   doc?: Doc
-): Promise<[cheerio.CheerioAPI, SourceCodeError[]]> {
+): Promise<[cheerio.CheerioAPI, SourceCodeError[], any]> {
   const urlLC = url.toLowerCase();
   if (renderCache.has(urlLC)) {
     if (invalidateCache) {
       renderCache.delete(urlLC);
     } else {
       const [renderedHtml, errors] = renderCache.get(urlLC);
-      return [cheerio.load(renderedHtml), errors];
+      return [cheerio.load(renderedHtml), errors, undefined];
     }
   }
 
@@ -135,5 +135,5 @@ export async function render(
       allErrors,
     ]);
   }
-  return [tool.cheerio(), allErrors];
+  return [tool.cheerio(), allErrors, metadata];
 }