The angularjs.org site is not designed to be used by third parties. It is only kept here as part of our own deployment processes.
If you want to have a go at hosting it yourself you can try running
yarn run build
This will build the website in the build folder, which you can then serve with something like:
yarn start
and browse to http://localhost:8080
Note: we do not provide support for doing this.
The site relies upon accessing numerous additional resources from all over the web.
Hint: to access the AngularJS docs application rather than this site, which is only the homepage, clone the main project and build the docs yourself. See https://github.com/angular/angular.js/blob/master/CONTRIBUTING.md