Disable CKEditor by default on Drupal sites.

Drupal_disable_CKEditor_by_default.user.js

// ==UserScript==
// @name        Drupal disable CKEditor in Drupal by default
// @namespace   https://github.com/dan-sprog
// @description Disable CKEditor by default
// @version     1
// ==/UserScript==

(function(){

  if(typeof Drupal !== 'undefined' && typeof CKEDITOR !== 'undefined' && Drupal.behaviors.ckeditor && CKEDITOR.env.isCompatible) {
		CKEDITOR.env.isCompatible = false;
		$(function(){
			$('.ckeditor_links')
				.show()
				.text('Enable CKEditor')
				.mousedown(function(){
					CKEDITOR.env.isCompatible = true;
					// Warning - Drupal.behaviors.ckeditor will not get called anymore.
					// Be careful of that because it might be doing something important.
				});
		});
	}

})();