I was surprised to find Web of Trust addon ( https://addons.mozilla.org/en-US/firefox/addon/wot-safe-brow... ) in top 10. From my past experience https://mywot.com is nothing more than a scam. Their ratings are not reliable and should not be trusted by anyone. For example, our business website was rated with "Child safety: Very poor" and there is nothing we could do about it.