Chris Lanphear

A very simple plugin to disable the Block Editor (formerly known as Gutenberg) and restore the classic WordPress editing experience. 
There are no settings. If Guten-bye is active, the Block Editor will be disabled for all registered post types and the original 
“Classic” editor will be used in its place.

Gutenbye

A very simple plugin to disable the Block Editor (formerly known as Gutenberg) and restore the classic WordPress editing experience.

Spencer Forman

54 lines of CSS that makes it easier to use the default editor in WP.

Fix Block Editor Style

Make Block Editor Look More Like Classic Editor.

Gutenbye vs Fix Block Editor Style