diff --git a/.gitignore b/.gitignore
index f8f8e69ff..0a89a9401 100644
--- a/.gitignore
+++ b/.gitignore
@@ -291,6 +291,7 @@ Thumbs.db
 
 # ignore local cert
 /lib/PuppeteerSharp.TestServer/testCert.cer
+/lib/PuppeteerSharp.TestServer/testKey.pem
 /lib/PuppeteerSharp.Tests/Screenshots/
 
 demos/PuppeteerSharpPdfDemo/google.pdf
diff --git a/lib/PuppeteerSharp/Cdp/CdpBrowser.cs b/lib/PuppeteerSharp/Cdp/CdpBrowser.cs
index 00f2d9cdd..2c79b1716 100644
--- a/lib/PuppeteerSharp/Cdp/CdpBrowser.cs
+++ b/lib/PuppeteerSharp/Cdp/CdpBrowser.cs
@@ -134,7 +134,7 @@ public override async Task<IBrowserContext> CreateBrowserContextAsync(BrowserCon
             "Target.createBrowserContext",
             new TargetCreateBrowserContextRequest
             {
-                ProxyServer = options?.ProxyServer ?? string.Empty,
+                ProxyServer = options?.ProxyServer,
                 ProxyBypassList = string.Join(",", options?.ProxyBypassList ?? Array.Empty<string>()),
             }).ConfigureAwait(false);
         var context = new CdpBrowserContext(Connection, this, response.BrowserContextId);