Just noticed the ChatGPT desktop app (previously named Codex) bundles a full copy of the LibreOffice open source office suite, tucked away in a hidden folder in the ~/.cache directory
(if you weren't already aware: office formats are basically just a zip archive containing a bunch of XML files. Try changing the filetype of a .DOCX to .ZIP and see what's under the hood for yourself)
I should have been more specific: what’s the smallest build that is currently buildable from their source repository? eg do they ever build a CLI or other minimal build as part of any product or even test framework?