Rated 4 out of 5 stars

I appreciate the no-restart nature of this extension, but I believe RefControl is still superior because of a toolbar button allowing easy disabling/enabling and access to per-site rules.

Four stars for a well executed extension, but no five because of the lack of any gui.

EDIT: The developer replied to my review before I edited to remove a silly mistake I'd made, which is what he references in #2. The lack of GUI is by design to prevent people who don't know what they're doing from modifying the extension's behavior. He mentions a way to create a button using Custom Buttons, but the created button will not inform the user via a pressed state or icon change of the enabled/disabled status of Smart Referer. RefControl users who do not create a lot of per-site rules may find Smart Referer to be a simpler solution for them.

This review is for a previous version of the add-on ( 

1. There are other addons that are made for that particular reason, if you look at the homepage you will see how to achieve that with Custom Buttons.
2. This is exactly what this addons does, this is not a general refer handling addon, it's specifically made to provide smart referers, which are made for 3rd party requests. RefControl version of smart referers is just a `referer.host == url.host`.

This addon was *never* made to have a GUI or have many options, you should use it as it comes and change behavior only if you know what you're doing.

To be even more clear, Smart Referer is not in competition with RefControl, they are two completely different addons and they do different things.

Nonetheless using both at the same time will break one or the other, if not both.

Thank you for the review.