mac 证书无法再“system root” 打开

提示“system root”无法打开密钥，我们需要手动的吧“。cer”文件拖到登陆密钥中。，如图

ref:

I've just had the same problem. For some reason Keychain Access wants to add to the System Roots keychain if you double click on the certificate. The only way round I found was to drag and drop on to a specific keychain, so "System" for AppleWWDRCA.cer and "login" for my development certificate.