All right, so again, you are mixing testing with stable without consideration of what I've told you that you should do before you do that, in a way that can mess up your system. And you did not even check the safe option, of installing new kernel from jessie backports. Or, perhaps even newer firmware package for your card, if it exists in backports. Or, also pretty safe option, of upgrading to stretch and getting newer packages, including new kernel, new firmware and new network-manager. Perhaps someone else will do better job in helping you, all that is left for me is to wish you good luck
