I fear I was to early too say that the update went fine, as problems showed themselves later by user feedback.
When someone first loads the page (or an article from a link) they get only shown it until after first post meta. Then page load stops. If the user reloads the page it is shown completely. It looks like the page only loads when a Classicpress cookie is set. I can replicate that by disallowing cookies from the site, in that case it never loads. I did not realize this because of course cookies from my site were set on all my computers.
I tried deactivating all plugins one ofter the other, but that did not help. I looked into the console in Chrome, but there’s nothing here.
This seems to have something to do with a session cookie with limited life time. Regular visitors of my site can read the articles after one reload, the next day the problem ist back.
If you have a chance, it would be good to test this on a fresh site (start with WP, then migrate to ClassicPress and verify that the same problem still exists).
Cookie name: I generally know that. But above a member of the council suggested to do that, so I guessed he probably has occult knowledge…
test install: I’m sorry, I already lost over two days searching for the problem, I really have no additional time to setup a new installation and migrate that to CP.
OK, I don’t have time to do this right now either, unfortunately. I’ve added a new tag needs-testing so that we can track issues that need further investigation.