diff --git a/4.1-Extensions.md b/4.1-Extensions.md
index 6b731e6..7d6160c 100644
--- a/4.1-Extensions.md
+++ b/4.1-Extensions.md
@@ -43,6 +43,8 @@ This list covers privacy and security related extensions only. While we believe
 These extensions will not mask or alter any data sent or received, but may be useful depending on your needs
 
 * [uBO-Scope](https://addons.mozilla.org/firefox/addon/ubo-scope/) | [GitHub](https://github.com/gorhill/uBO-Scope)
+* [Behave](https://addons.mozilla.org/firefox/addon/behave/) | [GitHub](https://github.com/mindedsecurity/behave)
+   * monitors and warns if a web page; performs DNS Rebinding attacks to Private IPs, accesses Private IPs, does Port Scans
 * [True Sight](https://addons.mozilla.org/firefox/addon/detect-cloudflare-plus/) ✔ <sup>[Privacy](https://addons.mozilla.org/firefox/addon/detect-cloudflare-plus/privacy/)</sup> | [GitHub](https://github.com/claustromaniac/detect-cloudflare-plus)
    * Why would you want to detect CDNs? Read [this](https://github.com/claustromaniac/detect-cloudflare-PA/blob/master/README.md#motivation).
 * [mozlz4-edit](https://addons.mozilla.org/firefox/addon/mozlz4-edit/) | [Github](https://github.com/serj-kzv/mozlz4-edit)