The legacy RTE won't be available in the new Create Entries beta until after the code push, after which there'll be a preference pane for it. As a caution, it's the same RTE that's used in the old version of the update page, which is very old and very buggy in modern browsers and we have very, very limited ability to troubleshoot because of its age and the fact it relies on extremely outdated technology. It's the same thing as the draft autosave issue: we've been working on a more modern solution that won't have those limitations, but it's proven a lot more difficult than it looks like on the surface and needs us to finish a ton of modernization work first (which we are getting near the end of, thank God!)

I'm not sure what you mean by "the zero-height entry bug", but we're not prioritizing any fixes for the legacy update page -- our effort is going into getting the beta Create Entries page fit for purpose instead. If you can reproduce the bug after the code push in the beta Create Entries page and it doesn't have to do with the legacy RTE, can you give us steps to reproduce so I can make sure it's logged as an issue?

If it has to do with the legacy RTE, we know there are lots of bugs with it and we can't fix them because it's very old (and very buggy in modern browsers). We were holding off on adding a RTE to the beta Create Entries page until we could integrate a more modern RTE package, but the work has proven a lot more difficult than we could have predicted and needed us to do a lot of modernization work first because the state of the art has changed so much since the original RTE was integrated into the original update page and all the solutions have proven difficult to integrate. We are still working on the process, we just have hit the point where we need to retire the old codepath for the old update page and are trying to get the beta Create Entries up to feature parity as much as we can first.