What problem does this address?

In the new summary panel in the document settings, it is not obvious that the title and excerpt are editable fields.
They look like plain text.

What is your proposed solution?

Please re-consider the usability impact that removing visible and recognizable input fields have for users.

Please re-add a visible border or outline so that the fields can be recognized as editable input fields.

It is also not clear how to resize the excerpt field. It does accept more than one line, but it is not clear that it only expands when you write a text that is long enough.