Github Pages + Jekyll is free and reliabe. And it’s fun to use it to make a website.

Jest mock module feature can be used for mocking whole or part of packages in your project. Check out: https://jestjs.io/docs/manual-mocks

Here is the two videos:

After upgrading MacOS to Catalina, everytime opening a terminal, there would be a prompt saying:

This article is just a trouble-shooting blog. It’s rarely happen. After you even did a force renew by using