I like using ghcs for this as well! Or at least, I liked to - it's deprecated now, in favor of the new CLI which doesn't provide the same functionality.
The headline made me excited, the article left me disappointed. An offline mode that requires me to individually download the pages and database rows I’m expecting to need beforehand is not the kind of “offline mode” that meets my needs.
https://github.com/github/gh-copilot/commit/c69ed6bf954986a0...
https://github.com/github/copilot-cli/issues/53