Block Editor - Simple Site - & symbol not displaying correctly in post editor title area

[dhackneya8c]

Steps to reproduce

1. Starting at URL: https://wordpress.com/post/ on a simple site
2. Enter a post title including an & symbol
3. Publish post
4. Title within editor shows & instead of &, but displays & normally on the published post

What I expected

Ampersand character to remain in title display within editor.

What happened instead

Ampersand expressed as code instead in title display within editor. This does not happen on the live post, it's just within the editor.

Browser / OS version

Chrome / MacOS 10.15.6

Screenshot / Video

Context / Source

User reported this issue in chat. They had also encountered it occurring with apostrophes in titles, but I was not able to replicate that in testing. Does not occur on atomic sites.

[cathymcbride]

Duplicate of WordPress/gutenberg#20490. Closing in favor of the root issue.