Font Book new collections are disabled, will not enable

Hello, I am categorizing several thousand fonts in Font Book through collections. There are about 20 or so collections in there now, but new ones showed up greyed out. They will not enable via the right-click menu. I thought maybe there was a limit on the number of collections, and deleted one I wasn't using to free up space, but this did not solve the issue. The answer to any Mac weirdness is usually "trash prefs." But will that affect the font collections? And if there is an easier way to manage these I'm open to it. Thank you