Problem/Motivation
The usability of ckeditor5 is degraded when editing a WYSIWYG field added to the form of a paragraph (paragraph module) and these conditions apply:
1. the field is part of a sub-form that is added dynamically to the form page (for example when adding a paragraph to a node page)
2. the ckeditor5 contains a big amount of text
3. when scrolling down on a page which has ckeditor5 active in this kind of form, if the viewport scrolls past where ckeditor5's toolbar would no longer be visible it is detached and made to stick to the top of the viewport. This conflicts with the standard toolbar so that the toolbar is partially hidden.
This seems ad edge case of this solved issue: #3259380: CKEditor 5's toolbar occludes Drupal's toolbar if and only if CKEditor 5 has focus
Steps to reproduce
1. enable ckeditor5 module, add a format that uses it
1. install the contrib paragraph module
2. create a paragraph type that includes a text-long field that uses ckeditor5
3. create a content type with a paragraph field, allow the paragraph type created in 2. to be added to the content type
4. create a new node of the content type
5. add a paragraph of the type defined in 2. to the page
6. add a big amount of text, so that the ckeditor window gets longer than the viewport
7. scroll up, observe the toolbar overlapping with the drupal toolbar
