Garageband 10.4.1 Download [portable]

Released in late 2019, 10.4.1 focused on stability and minor improvements over 10.4:

You can typically download or update to the latest version of GarageBand through the Mac App Store GarageBand - App Store - Apple Garageband 10.4.1 Download

If you are looking for this specific version, it introduced several major updates: Released in late 2019, 10

For the first time, users could customize region colors directly in their tracks for better project organization. Released in late 2019