The page history API for retrieving page _content_ seems to be broken, and for v2 nonexistent.
1. The ability to programmatically (using the Forge API) to access a prior version of a page no longer works.
2. The ability to obtain the _content_ of a prior version of a page, even by entering the URL query in a browser, no longer works.
E.g., this does not work using Forge: