With the upgrade to WordPress 5.0, the dashboard editor changed to a new interface called Gutenberg. This is a new visual style editor provided by WordPress. It changes the way WordPress edits pages and if you use the DIVI editor it will change the way you edit pages. This change can be disruptive if you’re not yet ready to learn the new features.
If you’re facing the problem of having to get things edited and you want to do so using the old familiar interface, here’s how to get things working as expected.
To get back the old editor for the Divi Theme, just go to Plugins -> Add New. Once you get in the plugins collection just search for Classic Editor in the search box.
Classic Editor is a free WordPress plugin which maintains by the WordPress Team to roll back the old (“classic”) WordPress editor and the “Edit Post” screen.
Once you got the Classic Editor plugin just click on Install Now and after the plugin is installed click on Activate to turn on the plugin.
You can also go to https://www.elegantthemes.com/blog/theme-releases/divi-and-wordpress-5-0 for more details from the creators of DIVI.