Rated 4 out of 5 stars

Does what it says on the tin!

Potential improvements:

1. Option to delete emails by matching just the address (e.g., vote@candidate-name.us), instead of the full RFC 5322 name-address, (e.g., "Elect Candidate Now!" <vote@candidate-name.us>). Political campaigns and brands routinely change the display-name so each deletion hits only one email out of dozens with the same address.
2. After deleting emails, dismiss the dialog, because the email for which you opened it doesn't even exist any more.

This review is for a previous version of the add-on (2.6.1).