How can they post this obviously internal thing from Google? How can they get clearance from security/IP?
As the team had to collaborate with the VSCode team, we got clearance for sharing information about it. The screenshots in the article were posted publicly on GitHub (in vscode issues). You can also find screenshots in https://research.google/blog/smart-paste-for-context-aware-a...
More generally, a lot has been communicated on developer infrastructure at Google.
I think many VSCode users are not familiar with the Comments UI, but it's used in e.g. the "GitHub Pull Requests" extension. Apart from that, some changes in the list of directories/files (for performance reasons) and a redesigned SCM integration.