Installing the Altspace uploader is something that might take you a few minutes to struggle with the first time you attempt to add the uploader if you are new to Unity. Once you have done this process a few times it becomes second nature and is easy to do in reverse to remove the package uploader if you can’t automatically update in the future.
Adding the uploader to the package manager
Window > Package Manager > Add package from tarball Then find the uploader you have downloaded. You will need to login and depending on the uploader you have you may need to click update and restart your project if your uploader is very out of date.