How to allow custom HTML tags in the CKEditor 5 of TYPO3 12?

According to the changelog, the CKEditor 5 plugin "GeneralHTMLSupport" is available in TYPO3 12. I guess it can be activated in the own editor configuration (yaml):

imports:
  - { resource: 'EXT:rte_ckeditor/Configuration/RTE/Processing.yaml' }
  - { resource: 'EXT:rte_ckeditor/Configuration/RTE/Editor/Base.yaml' }
  - { resource: 'EXT:rte_ckeditor/Configuration/RTE/Editor/Plugins.yaml' }

editor:
  config:
    ???

Unfortunately, the examples from the CKEditor 5 documentary, like …

htmlSupport: {
    allow: [
        {
            name: 'div',
            classes: true
        }
    ]
}

… does not work here.

How can I allow <div class="xyz">…</div> in the RTE, for example?

Addendum: As I have just learned, it cannot work at all yet due to the bug https://forge.typo3.org/issues/100861. Nevertheless, I would be interested to know how to configure it after the bug fix is implemented.

As David mentioned in the comment above, it now works since TYPO3 version 12.4.7. as described in the docu:

EXT:my_sitepackage/Configuration/RTE/MyPreset.yaml

# Allow the <iframe> tag with all attributes, all classes and all styles:
RTE:
  config:
    htmlSupport:
      allow:
        - { name: 'iframe', attributes: true, classes: true, styles: true }