Add classic-editor query parameter to redirect editor URL
Add classic-editor query parameter to redirect editor URL

WordPress.com continues to push the new block editor and now redirects
wp-admin editor links to the block editor. The classic-editor query
parameter is necessary to prevent the redirect.

https://wordpress.com/blog/2020/08/13/the-classic-editing-experience-is-moving-not-leaving/

tpenguinltg/wpcom-edit-post-redirect.user.js