If you add an action and then another one after, you can't delete the action fully. It turns to "No Action", but it's still there in the list of actions.
Version: 3.994
That has been on my TODO list for a long time. It's due to a limitation in the data model which dates back to 2009 
when BTT looked like this and the Apple world was much simpler.
Currently you can get rid of the "No Action" by dragging the other actions up.
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