🇺🇸United States @Larry Jones

I still see this issue in Drupal 10.2.7, when I switch from ckeditor4 to ckeditor5.

In Structure | Content types | custom1 | Manage fields | Default value | Body field, this line:

<ul class="iti" data-toc="div.fyi">
</ul>

allows my custom javascript to build a table of contents of header tags within div class="fyi"

This has worked fine with ckeditor4 through multiple drupal versions. However, ckeditor5 removes the ul tag, so no ToC is built.