How to Delete unused Theme
Simple as 1-2-3:
Click on Appearance-Themes
Hover mouse above unused theme to see option “Theme Details” – click on it.
You will see “Delete” option in the bottom-right corner. Say OK on the next Pop-up.
Click it and enjoy 🙂
Why delete unused theme?
Unused themes may provide attackers a doorway to intrude.
Also, best practice is not to keep stuff that you do not use.