You can disable TLS cert verification when going through a proxy in VSCode. There is an option to disable “strict SSL”. Then I run a man-in-the-middle HTTP proxy and capture the traffic.

Also possible when using the Vim copilot plugin (or its emacs port) which is pretty informative - you can see a lot of the extra tricks the VSCode implementation uses.

Proxyman is a fantastic piece of software for this on Max, there’s a free version which can snoop on up to 6 apps at a time (it installs a root certificate)