Describe the bug

On WordPress 5.8 the error You attempted to edit an item that doesn't exist. Perhaps it was deleted? when the user after saving the template, keeps staying in the template editor and refresh the page.

To reproduce

Steps to reproduce the behavior:

1. Open the FSE editor
2. From the sidebar on the left click on Templates.
3. Click on one of these templates Product Category Page, Product Archive Page, Product Archive Page or Single Product Page. (check that it is not a modified template )
4. Edit the template and save it.
5. Refresh the page.

Expected behavior

The user can refresh the editor and continue to edit the template.

Screenshots