diff --git a/packages/openclaw-bridge/src/openclaw-client.ts b/packages/openclaw-bridge/src/openclaw-client.ts
index d2ea8b5..6ce14c4 100644
--- a/packages/openclaw-bridge/src/openclaw-client.ts
+++ b/packages/openclaw-bridge/src/openclaw-client.ts
@@ -54,7 +54,7 @@ type Frame = ReqFrame | ResFrame | EventFrame;
 // ── Helpers (mirror openclaw/openclaw internals) ──────────────────────────────
 
 function base64UrlEncode(buf: Buffer): string {
-  return buf.toString('base64').replaceAll('+', '-').replaceAll('/', '_').replace(/=+$/g, '');
+  return buf.toString('base64').replace(/\+/g, '-').replace(/\//g, '_').replace(/=+$/g, '');
 }
 
 // Ed25519 SPKI prefix (ASN.1 DER) — 12 bytes