@Drivingralle reported this on Core 63789:

How to reproduce it:

• Open a new playground
• Open "Hello World" post in block editor from admin bar or post list in WP-Admin
• Disable "full screen mode"
• Insert some block(s) and convert them to a synced pattern
• (Save post)
• Enter edit mode for that synced pattern via "Edit original" in tools bar
• Click "View post" button in admin bar

I was expecting to view the "Hello World" post or that the link inside the admin bar to be hidden as long as I'm editing the synced pattern.

Here a video showing it:
https://cloudup.com/cJS7LS3fSub