Where can I cleanup typo content of custom metadata?

For example, I created a custom metadata “Author”, but I have a typo when input in. Then in the value list of “Author”, will show up the typo value. How can I clean it up?

In the Inspectors pane under i/Custom you can find the Author data for an item and there you can correct it too. If that’s what you were asking for.

If the custom metadata name itself contains a typo you can correct that in the Data section of the preferences by renaming the custom metadata.

For example, how can I remove “m” in the list?