This looks like it would be an amazing extension and looks like it would greatly benefit me. However it is closed-source, and being as such, I am not able to check the source code for malicious functionality as any open source user of software that deals with private information should. I simply can't trust an extension that operates solely on user's private information such as credit card numbers, passwords and addresses that is closed source. Not to mention all the other reasons to be open-source, both for developers and users alike.