diff --git a/lib/internal/http.js b/lib/internal/http.js
index 9bf929f7f33..e664663348a 100644
--- a/lib/internal/http.js
+++ b/lib/internal/http.js
@@ -156,7 +156,7 @@ class ProxyConfig {
       if (entry === host || entry === hostWithPort) return false;  // Matching host and host:port
 
       // Follow curl's behavior: strip leading dot before matching suffixes.
-      if (entry.startsWith('.')) {
+      if (entry[0] === '.') {
         const suffix = entry.substring(1);
         if (host.endsWith(suffix)) return false;
       }