Rated 3 out of 5 stars

per Davide el abr. 13, 2022 ·

Sends details of your e-mail senders IP-addresses, and also other personal info to their service... bad privacy unfortunately.

See the privacy policy: https://www.mailhops.com/privacy/

EDIT:
Well, this is quite broad and vague... hence my low star rating:

"We may get information about how and when you use the Services, store it in log files associated with your account, and link it to other information we collect about you. This information may include, for example, your IP address, time, date, browser used, and actions you’ve taken within the application."

This review is for a previous version of the add-on (4.3.0). 

per Andrew Van Tassel (desenvolupador) a abr. 13, 2022 ·

MailHops uses IP addresses from the email headers to do GeoIP lookups, there is no personal information sent.