This extension completely replaces Strapi's Wysiwyg editor by Tinymce.
This extension has been created based on the same CKEditor tutorial. You can find this information here https://strapi.io/documentation/v3.x/guides/registering-a-field-in-admin.html
CKEditor in the latest versions has removed the options to add HTML code, and that's why among other things I preferred to use Tinymce.
This extension also includes the button to add images from the Media Library and also in the cursor position
npm install --save @tinymce/tinymce-react
Copy the content-manager directory to your extensions directory
In addition, download the Tinymce prod files from https://www.tiny.cloud/get-tiny/self-hosted/ and add them to the public folder.
We need to download it because if you don't you will receive an error in the editor that you need a cloud api key, and we want to use it for self-hosted.
This configuration along with all the options can be seen here https://github.com/chiqui3d/strapi-tinymce/blob/master/content-manager/admin/src/components/WysiwygWithErrors/Tinymce.js#L25