diff --git a/scripts/verify-web-performance.mjs b/scripts/verify-web-performance.mjs
index 435a6813..8ba15b4f 100644
--- a/scripts/verify-web-performance.mjs
+++ b/scripts/verify-web-performance.mjs
@@ -52,7 +52,8 @@ const allowedLargeChunkPattern = /^(?:vendor-(?:code-highlight|beautiful-mermaid
 // while retaining the initial preload budget and the checks below.
 const boundedDeferredChunks = [
   { pattern: /^vendor~mathlive-loader-.*\.js$/, maxBytes: 850 * 1024 },
-  { pattern: /^i18n-ja-.*\.js$/, maxBytes: 525 * 1024 },
+  // Poster editing adds localized controls; the current catalog is ~527 KiB.
+  { pattern: /^i18n-ja-.*\.js$/, maxBytes: 530 * 1024 },
 ];
 const allowedLargeChunk = ({ name, size }) =>
   allowedLargeChunkPattern.test(name) ||