I had deleted all feeds and wanted to import an OPML file.
I was getting that little toast over the + icon to add my first feed, but I preferred to do an import. However, the gear was unclickable. I tried on Chrome, and Firefox. Had all extensions that could have messed with it off.
Ended up having to use the mobile up to import the OPML. And it was only then that the gear was clickable back on desktop.
An odd bug. But perhaps it’s an unintentional side effect of the OOBE? Still, a bother for experienced users.