This plugin is a Premium extension for Classic Editor and Classic Widgets free plugin.
The free version of this plugin helps you to easily disable Gutenberg Editor totally everywhere and enables Classic Editor and Classic Widgets. Also, free plugin enables old-style WordPress Classic Editor for “Edit Post” with TinyMCE (WYSIWYG), Meta Boxes (Custom Fields), and others. Once activated, this plugin hides all functionality available in the new Gutenberg block editor.
Here you can see how Free Version works: