The application display the articles (Tips) when delete the category associated

REPRODUCIBILITY LEVEL:
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Always

STEPS:
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You need to create a new tip first

Steps
1. Expand the control panel
2. Select "Configuration >> Tips Pf The Day
3. Delete the category associated
4. Click on the save button
5. Click on the Tips of the day icon
6. Click on "Show me tips now"


CURRENT RESULT:
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The application display the articles (Tips) when delete the category associated
https://screencast.com/t/yKk1aEjROUha

EXPECTED RESULT:
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The application don't display the articles (Tips) when delete the category associated