Underline with "error waves" new tags when adding note

When adding a new notes, it happens that I misstype a tag, and I only realize my mistake once I filter the notes in the browser by tag and realize I have several times the same tags, with mistakes.

To prevent this, without removing the easiness of adding a tag just by writing a new one, the new note editor could underline the newly created tags (or have any visual indication), so that you don’t create one by accident.