--- a/netwerk/base/nsIOService.cpp
+++ b/netwerk/base/nsIOService.cpp
@@ -1617,16 +1617,18 @@ nsIOService::OnNetworkLinkEvent(const ch
         LOG(("nsIOService::OnNetworkLinkEvent mManageLinkStatus=false\n"));
         return NS_OK;
     }
 
     bool isUp = true;
     if (!strcmp(data, NS_NETWORK_LINK_DATA_CHANGED)) {
         mLastNetworkLinkChange = PR_IntervalNow();
         // CHANGED means UP/DOWN didn't change
+        // but the status of the captive portal may have changed.
+        RecheckCaptivePortal();
         return NS_OK;
     } else if (!strcmp(data, NS_NETWORK_LINK_DATA_DOWN)) {
         isUp = false;
     } else if (!strcmp(data, NS_NETWORK_LINK_DATA_UP)) {
         isUp = true;
     } else if (!strcmp(data, NS_NETWORK_LINK_DATA_UNKNOWN)) {
         nsresult rv = mNetworkLinkService->GetIsLinkUp(&isUp);
         NS_ENSURE_SUCCESS(rv, rv);