It would be possible to generate basic API documentation from the IDL the browsers actually use internally. It would not necessarily be completely accurate beca

It would be possible to generate basic API documentation from the IDL the browsers actually use internally. It would not necessarily be completely accurate because sometimes browsers don't use IDL for their features, but it would be another tool, and would have helped in this case. You wouldn't need to even be a member of the browser team to do this, since the relevant data is all open source.