Along with the usual minor improvements and bug fixes, WordPress 5.0 introduced a new page editor: Gutenberg, a new Theme Template: Twenty Sixteen and a new Plugin.
For more information about the latest version of WordPress 5.0 - "Bebo" see the following Blog post:
Classic Editor Plugin
The new Gutenberg editor introduced in WordPress 5.0 while a major improvement, has also been found to cause problems with some theme page editors. Fortunately, WordPress has also released a new Plugin that allows WordPress users to revert the page editor to the previous default page editor. For more information and instructions on installing the new Classic Editor plugin, see the following Knowledgebase article:
If you should need additional assistance submit a Support Request here:
Domingo, Deciembre 9, 2018