How should I use my assigned CA certificate?

[hurriedlu]

I self-signed a lot of ssl certificates on my old computer and exported CA certificates and installed him on other devices to enable trusting websites that use self-signed certificates. Now I got a new computer and when I self-signed the certificates using the backup mkcert software, I found that the computer doesn't seem to trust the new self-signed certificates. Is there any way to make mkcert use the existing ca certificate for signing?