Dead link on https://github.com/rmottola/Arctic-Fox

[InfoLibre]

The link toward Mozilla Source Code Directory Structure and links to project pages is a dead link on https://github.com/rmottola/Arctic-Fox page. I found these two pages, maybe the first is the good one?

https://www.devdoc.net/web/developer.mozilla.org/en-US/docs/Mozilla_Source_Code_Directory_Structure.html

https://firefox-source-docs.mozilla.org/contributing/directory_structure.html

[rmottola]

dev branch incorporates suggested fixes