Review for MailHops by Apollo!
Rated 5 out of 5 stars
I installed it the other day and it did accurately trace numerous emails and their routes. A few got the locations off by maybe 20 miles( usually naming a neighboring town) but in general it was extremely close. I tested it out with mails from many places- including international and it got them correct too. If there are any significant flaws I have yet to see them. So therefore so far so good!
This review is for a previous version of the add-on (0.5).To create your own collections, you must have a Mozilla Add-ons account.