If a recipe exists but is not associated with a corpus it will still say ‘Processing’ for that Recipe in the Matches tab, even if it will never return a classification.

How to reproduce:
Open up web extension pop-up
Add a recipe (just a name, like Foo)
Go back to Matches tab
It says: “Foo: Processing”, but it’s not processing. Should say something more descriptive as a first level, but could also add some form validation to make sure a recipe is always associated with a corpus.