How to manage keywords created in Photos

I have a large library of Photos (ok, large to me, it`s about 5-6k fotos with multiple keyword tags that helps me to find images associated witch some idea, person or thing.

When i am applying this keywords to photos individuals metadata, it recognizes my typing and show tags (keywords) that fit with what i typed, then i press <enter> and it`s done. It˜s marked/labeled/tagged/keyworded...

Sometimes, system does not show the keywordlist before i hit <enter> after type some two or three letters, then a partial tag, as "#nat" from #nature, is created and i cannot erase it anymore. Even if i remove from all images, it continuously are exhibited on tags listing when i start to type...

Theres a way to exclude/delete tags/keywords that are not in use from Photos cache?

Thanks in advance.

Fernando P.

Brazil

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