mimeTypesLower.Store(k, v)
	}
	for k, v := range mixExt {
		mimeTypes.Store(k, v)
	}

	extensionsMu.Lock()
	defer extensionsMu.Unlock()
	for k, v := range lowerExt {
		justType, _, err := ParseMediaType(v)
		if err != nil {
			panic(err)
		}
		var exts []string
		if ei, ok := extensions.Load(justType); ok {
			exts = ei.([]string)
		}
		extensions.Store(justType, append(exts, k))
	}
}

	}
	return nil
}

// ErrInvalidMediaParameter is returned by [ParseMediaType] if
// the media type value was found but there was an error parsing
// the optional parameters
var ErrInvalidMediaParameter = errors.New("mime: invalid media parameter")

// ParseMediaType parses a media type value and any optional
// parameters, per RFC 1521.  Media types are the values in