[throwaway4good]

Isn't Google chrome open source?

It should be possible to point to the source code of whatever google.com extensions that may exist.

Or is this only available in the packaged distributions of Chrome?

[throwaway4good]

https://chromium.googlesource.com/chromium/src.git

[poikroequ]

I think there are a few bits and pieces which may not be open source, such as those for DRM.