0 Stars! Why? Because: "browser extension, created by iDavis". In my opinion, this extension looks like a copy of ElvenAssist. The appearance is different, but it’s an extension—it has the inventory, and you can load the city into the city planner. The creator of the original extension put a lot of time and effort into it, and the “Elvenar Tools” extension doesn’t give them any credit at all. Even the in-game logo for opening the extension is in the exact same spot.

It's also misleading to me not to specify that the extension is a fan project (or isn't it?), especially when you're even using the trademarked “Elvenar” logo on the extension. This gives to me the impression that the extension (and the Elvenar Tools) are from Elvenar / InnoGames.—or did it? In my view, “supported by Elvenar” and “by Elvenar" are two different things.
I can only give 1 star to an extension that I believe is andoring itself with someone else’s feathers. If I could, it would be none. I’ve removed the extension.

@iDavis - Question: ¿Did you really use the publicly available code? And then that: "... created by iDavis."??? "Elvenar Tools - All rights reserved" ??? I just don’t get it!
Now elvenstats, too? What's next, iDavis? Is your goal to go from being the creator of a popular fan site to becoming a plagiarist… an imitator? Under the name “Elvenar”? Under their protection and guidance? Aren't you aware of that?
EDIT - My opinion is: Those who remain stoically silent have either been muzzled or have no arguments to prove otherwise!