bug(rich-text) no highlight on selected HR element

[yellis]

Describe the bug
In rich text mode an horizontal rule

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does not have a selection highlight whereas surrounding paragraphs have it.

To Reproduce

1. RT mode. Type some text, add a HR, type some more text
2. Select all text.
3. Observe that there is nothing indicating that the HR is selected. If you delete, it is all gone
4. Also possible to select the bottom text and the HR, but not the top text. Deleting will delete the HR and the bottom text. So it is selected.

Expected behavior
Some visual indicator when the HR is selected

Desktop (please complete the following information):
Windows 11 Chrome 103

Additional context
https://meta.stackexchange.com/a/380447/51