How to Disable WordPress Gutenberg Editor

First, install and activate the Classic Editor plugin on your site.

After activating, this plugin will automatically disable Gutenberg Editor from WordPress 5.0.

The best thing about this plugin is that you can use both Gutenberg and Classic editor on your site.

Just go to Settings >> Writing section. Here you will see the option of Classic editor settings.

If you select the second checkbox “Use the Gutenberg editor by default and include optional links back to the Classic editor”, the plugin will add the Classic Editor option within the Posts menu.

Apart from this, you can also edit old articles using the Classic editor. Just click on Posts >> All Posts, here you will see an Edit (Classic) link at the bottom of the post.