Go to the Edit...inclusions subtab, type some things in, and click save:



actually this is the wrong diagnosis.  The issue is not the inclusions, which you can edit fine if you go directly to the can't save from inclusions subtab card.  It has something to do with nesting in several layers deep (and might be connected to breakage from autosave failures?).  I've seen this before on Decks.  We should keep watching this, but this ticket needs refactoring.