Smart Referer is described as 'Send referers only when staying on the same domain. You can whitelist domains with wildcards and configure other things, look in the preferences page of the addon in the addon manager' and is an app in the web browsers category. There are three alternatives to Smart Referer for a variety of platforms, including Mac, Windows, Linux, Android and Mozilla Firefox apps. The best Smart Referer alternative is RefControl, which is free. Other great apps like Smart Referer are Referer Control and Auto referer.
RefControl is an extension for Firefox that lets you control what gets sent as the HTTP Referer on a per-site basis.
RefControl is the most popular Windows, Mac & Linux alternative to Smart Referer.
RefControl is the most popular free alternative to Smart Referer.
Referer Control grants full control over the HTTP Referer. You can forge any referrer you want, both globally or on a per-site basis. Alternatively you can choose to disable the Referer completely. Also works on the JavaScript document.referrer!
Referer Control is the most popular Android, iPhone, iPad & Android Tablet alternative to Smart Referer.
An Firefox addon to supress HTTP header's referer, to protect some privacy and try not breaking the web.
Auto referer is the most popular Open Source alternative to Smart Referer.
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