I am running Ubuntu 18.10 (installed from mini iso) with Plasma desktop 5.13.5 (from the repositories.) I always do updates on the command line without any issues. sudo apt update && sudo apt dist-upgrade shows that there are no updates, yet Discovery shows there is an update "GNOME Application Platform version 3.32". I have not taken this update.
The Discovery icon always shows 1 update pending, but sometimes when I open Discovery it says there are no updates. This GNOME update seems to come and go but still, apt never sees it.
How can I figure out what is going on here?