VPN-6228: Do not tear down tunnel if server becomes unavailable

src/controller.cpp

@@ -300,14 +300,15 @@ void Controller::serverUnavailable() {
   // to deactivate the VPN in the case of server location becoming unavailable
   // because the user may not notice that they are no longer protected which can
   // cause the traffic to leak outside the tunnel without their knowledge.
-  if (m_state == StateOn) {
+  if (m_state == StateOn || m_state == StateSilentSwitching ||
+      m_state == StateCheckSubscription) {
     return;
   }
 
   m_nextStep = ServerUnavailable;
 
   if (m_state == StateSwitching || m_state == StateConnecting ||
-      m_state == StateConfirming || m_state == StateCheckSubscription) {
+      m_state == StateConfirming) {
     logger.info() << "Server location is unavailable and we are not in "
                      "StateOn. Deactivate!";
     deactivate();