# Update Manager test plan 1. If `apt list --upgradable` returns nothing, downgrade a package in the system. #### TIP Of course it’s better to do so with a cosmetic package that has no chance to impact the system, e.g. [`cowsay`](https://launchpad.net/ubuntu/+source/cowsay/+publishinghistory). 2. Start `update-manager`. 3. Verify that `update-manager` suggests packages matching the output of `apt list --upgradable`. #### NOTE If the list is too long, just scanning over the output is OK, as Apt will list package names and Update Manager their short descriptions and that makes a one-by-one comparison very slow. 4. Install one or more updates via Update Manager, verify that the corresponding packages are gone from * `apt list --upgrade`; and * `update-manager`’s recalculated view.