if(prevBufferId.isValid() && _chatViews.contains(prevBufferId)) {
MsgId msgId = _chatViews.value(prevBufferId)->lastMsgId();
Client::setBufferLastSeenMsg(prevBufferId, msgId);
if(prevBufferId.isValid() && _chatViews.contains(prevBufferId)) {
MsgId msgId = _chatViews.value(prevBufferId)->lastMsgId();
Client::setBufferLastSeenMsg(prevBufferId, msgId);