diff --git a/test/e2e/upstream-proxy.feature b/test/e2e/upstream-proxy.feature
index c813f8cf3..e672592f7 100644
--- a/test/e2e/upstream-proxy.feature
+++ b/test/e2e/upstream-proxy.feature
@@ -6,6 +6,7 @@ Feature: UpstreamProxy
   Scenario: UpstreamProxy
     Given a configuration with:
       """
+      browserDisconnectTolerance: 3,
       files = ['behind-proxy/plus.js', 'behind-proxy/test.js'];
       browsers = ['ChromeHeadlessNoSandbox'];
       plugins = [