Plugins not showing in widget area

I’m having trouble since the latest updated. None of the new plugins that I’ve installed since then (and a couple that I had installed before) are showing up in the “available widgets” area. The plugins work fine under their settings, and there are a couple that I downloaded to test that were compatible with the new WP version, but I can’t get anything new to show up in the “available widgets” are except for the default WP widgets.

I have tried deactivating and reactivating all plugins that I’m using and that has not helped.