There are two Extra Objects addons that ship with Blender and just need to be enabled in Preferences to use.
One is for adding Mesh objects of various shapes. The other is for adding different kinds of Curve objects.
It seems that at some point (maybe during the transition from Blender 2.79) the presets in the Operator Panel for these addons went missing. I can still use the addons, but the Operator Presets are missing. Additionally, there is an option to "Restore Operator Defaults" that doesn't work.
I'm just wondering if this is the same for other people, or if I did in ~/Library something to screw up these addons, or if it's a bug that has somehow gone unnoticed, or if I need to download some dependencies from the developer, or... well you get the idea. It raises questions. If anyone knows why the presets are missing or how to fix it, please share.