Over the past two months, Andigo has worked with clients to evaluate and update their sites with the newest version of WordPress. (Version 5.1 was released late last week; we have been updating to 5.0.3 to date. We’ll recommend update to 5.1 once we have have reviewed for stability, compatibility, and vulnerabilities.)
Gutenberg is a visual editor. Though visual editors have been available as plugins and theme elements for many years, Gutenberg is the first visual editor to be made a part of WordPress by default.
Not all themes and plugins are compatible with Gutenberg, and not all sites will play nicely with it. (Or any other visual editor.) For this reason, you can override Gutenberg to remain with the “Classic” editor. (This ability will remain for at least the next year but Gutenberg may become the only option at some point in the future.)
If you aren’t sure about your site’s compatibility, we’d be happy to help you evaluate it. We strongly recommend that you do not test the new editor on your live site. Set up a staging server and test thoroughly. And, of course, create a back up of your site before you begin.