--- a/toolkit/components/extensions/test/mochitest/test_chrome_ext_native_messaging.html
+++ b/toolkit/components/extensions/test/mochitest/test_chrome_ext_native_messaging.html
@@ -123,19 +123,19 @@ while True:
     sys.stdout.write(struct.pack('@I', msglen))
     sys.stdout.write(msg)
 `;
 
 const STDERR_LINES = ["hello stderr", "this should be a separate line"];
 let STDERR_MSG = STDERR_LINES.join("\\n");
 
 // Python apparently line-buffers stderr even with the -u arg on
-// Windows 7.  Dealing with that is more hassle than its worth but
+// Windows.  Dealing with that is more hassle than its worth but
 // on other platforms, we want to keep testing partial lines.
-if (AppConstants.isPlatformAndVersionAtMost("win", "7")) {
+if (AppConstants.platform == "win") {
   STDERR_MSG += "\\n";
 }
 
 const STDERR_BODY = String.raw`
 import sys
 sys.stderr.write("${STDERR_MSG}")
 `;