I have CKEditor installed and much prefer it. Upon attempting to write a new entry today I found post-new.php yielded just a blank page. Then through my mental fog came the realization that WordPress has been threatening to cut in Project Gutenberg recently. Additionally I realized that CKEditor plugin often conflicts with other plugins. So upon disabling it I saw the new interface. Ok no thanks. I googled and found the following officially supported WordPress plugin.
I was a little surprised that WordPress must be automatically updating my php scripts because I run on my own servers. The update process is detailed here: