[Drupal] How to test the CKeditor configuration on a Drupal / non-Drupal website?

CKEditor is a WYSIWYG editor plugin that can be integrated into any Drupal / Non-Drupal website. Integrated with complex and comprehensive features,this text editor simplifies website content creation and is very helpful for content editors. Following are a few of the key things that need to be considered, while testing CKEditor implementation on Drupal websites.

1. Ensure that all the buttons on the toolbar of CKEditor is functioning.
2. Ensure that the formatting given on the content edit page is the same as reflected on the content view page.
3. Ensure that the editor shows up for people with permission to use CKEditor.
4. Ensure that the pages created with CKEditor gives valid HTML.
5. Ensure that users without the proper permission do not get access to the CKEditor.
6. Ensure that CKEditor shows up only in required fields.
7. Ensure that only required buttons show up in the CKEditor interface.

These are the things that, I believe, should be considered during the testing process. Do you think I have missed something? Let me know using the Comments box below.