Potencially harmfull Rated 1 out of 5 stars

I consider this extension potencially harfull to your data and confidentiality of your credentials.
This extension is sending your URLs to some machine in Amazon cloud.
It is not clear what is happening with the data then.
It can be potencially used to harvest your data straight after you log-in to vulnerable site after you have been told the site is clean.
This is only about the trust - how much you believe the one who is running the no-name machine in the cloud.

Best regards
Michal Ambroz

This review is for a previous version of the add-on (0.1.1-signed.1-signed). 

It does not send URLs. It sends hostnames, which in general can not be used to harvest data other than what hostnames a particular public IP has visited. If it bothers you, feel free to uninstall it.