First of all, just so you know, I would have selected "Popover" where it says "Pick a plugin or theme" but it wasn't available so I chose "Upgrades."
Now for the concern. I upgraded to Popover plugin 3.0 and then I went to the admin area. I was unable to remove any of the rules. When clicking on "Remove" nothing would happen, even if I clicked on "Update" later on.