Cannot test an unsaved rule

The test button should not be available if "Save" is required before being able to test a new rule. This confused me when I created my first rule. I typed it, pressed test, and tried an email that obviously should have triggered the rule. But nothing happened. At first, I thought the AI was failing to flag the email, but actually, I needed to first "Save" the rule and then I was able to successfully test the rule.