by p4wparamjeet on WordPress.org
Enables the previous "classic" editor and the old-style Edit Post screen with TinyMCE, Meta Boxes, etc. Supports all plugins that extend thi …

Admin settings on the Settings -> Writing screen.
Default Classic Editor is a plugin maintained by the paramjeet that restores the previous (“classic”) WordPress editor and the “Edit Post” screen. It makes it possible to use plugins that extend that screen, add old-style meta boxes, or otherwise depend on the previous editor.
Default Classic Editor is a WordPress plugin, and will be fully supported and maintained until at least 2022, or as long as is necessary.
At a glance, this plugin adds the following:
In addition, the Default Classic Editor plugin includes several filters that let other plugins control the settings, and the editor choice per post and per post type.
By default, this plugin hides all functionality available in the new Block Editor (“Gutenberg”).