Many project classes not showing up in palette/context menu

The issue we’re having is that many of the blueprint classes that exist in our project are not showing up within the right-click context menu in the blueprint editor, or in the blueprint palette.

The editor seems to not be loading these classes upon starting up. They still exist and are openable from within the Content Browser, and you can find them in the Class Viewer.

Once you open one of the classes via the Content Browser, OR right click on the class in the Class Viewer, that specific class becomes available within the Context Menu and the Palette.

This was not happening before, and appears to have no relation to how much memory our computers have available. We can work around it, but we can’t explain why it is happening. Anyone have any ideas?

In the attached image, each class with an unfilled circle icon next to it is not available for quick use in the context menu or the palette. Once I right-click on that class, it becomes available, and the icon changes to the appropriate one for the class (see the NPC class near the top of the image).