From 7488001940428aab542c48aa3d50e0ca1c320ec3 Mon Sep 17 00:00:00 2001
From: Honza Bambas <honzab.moz@firemni.cz>
Date: Fri, 13 Apr 2018 10:04:00 -0400
Subject: [PATCH] Bug 1452028 - Bring back network.http.fast-fallback-to-IPv4
 preference, regression from bug 1430659. r=valentin

--HG--
extra : rebase_source : a33a72e2117f94aeb101eac8cd2b560fadfaae85
---
 netwerk/protocol/http/nsHttpConnectionMgr.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/netwerk/protocol/http/nsHttpConnectionMgr.cpp b/netwerk/protocol/http/nsHttpConnectionMgr.cpp
index 4551189c86b3..80d169a586b8 100644
--- a/netwerk/protocol/http/nsHttpConnectionMgr.cpp
+++ b/netwerk/protocol/http/nsHttpConnectionMgr.cpp
@@ -4087,7 +4087,7 @@ nsHalfOpenSocket::SetupStreams(nsISocketTransport **transport,
             socketTransport->SetTimeout(nsISocketTransport::TIMEOUT_CONNECT,
                                         fallbackTimeout);
         }
-    } else if (isBackup) {
+    } else if (isBackup && gHttpHandler->FastFallbackToIPv4()) {
         // For backup connections, we disable IPv6. That's because some users have
         // broken IPv6 connectivity (leading to very long timeouts), and disabling
         // IPv6 on the backup connection gives them a much better user experience