diff --git a/security/manager/tools/getHSTSPreloadList.js b/security/manager/tools/getHSTSPreloadList.js
index 26fad8a895..29f4ba4205 100644
--- a/security/manager/tools/getHSTSPreloadList.js
+++ b/security/manager/tools/getHSTSPreloadList.js
@@ -25,7 +25,7 @@ const SOURCE = "https://chromium.googlesource.com/chromium/src/net/+/master/http
 const OUTPUT = "nsSTSPreloadList.inc";
 const ERROR_OUTPUT = "nsSTSPreloadList.errors";
 const MINIMUM_REQUIRED_MAX_AGE = 60 * 60 * 24 * 7 * 18;
-const MAX_CONCURRENT_REQUESTS = 5;
+const MAX_CONCURRENT_REQUESTS = 15;
 const MAX_RETRIES = 3;
 const REQUEST_TIMEOUT = 30 * 1000;
 const ERROR_NONE = "no error";