Feature Request - Tag Proposal in Metadata Editor

I have a feature request for the metadata editor.

I have a predefined tag "Biography & Autobiography". If I start typing "bio..." I get automatically the proposal "Biography & Autobiography", so I can easily select it for the book.

BUT: if I start typing "auto..." nothing happens....and this is my feature request....getting also proposal for this.

Sorry, I do not know how to describe it better. See attached picture.

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