W3.css not loading

Hi,

Today most of my site design disappeared.

After some troubleshoot I found the issue. The file https://www.w3schools.com/w3css/4/w3.css was not loaded because the *.w3schools.com certificate was expired:

I solved the issue by copying the file w3.css to my custom theme and add it to the .libraries.yml file.

global-components:
  version: 0.1
  css:
    theme:
      css/style.css: {}
      css/w3.css: {}
  js:
    js/script.js: {}

We should have an option on the theme to have a copy of the files stored locally.

Thanks,
José