Howtoforge published a tutorial about creating a locally trusted SSL certificate with mkcert on Ubuntu 20.04.
How to Create Locally Trusted SSL Certificates with mkcert on Ubuntu 20.04
Mkcert is a free, simple, and very useful tool that allows you to create a locally trusted certificate without buying it from the real CA.
How to Create Locally Trusted SSL Certificates with mkcert on Ubuntu 20.04