diff --git a/guides/source/security.md b/guides/source/security.md
index 84ded55372..2a5e6b8ad7 100644
--- a/guides/source/security.md
+++ b/guides/source/security.md
@@ -579,7 +579,7 @@ This is alright for some web applications, but certainly not if the user is not
 
 Depending on your web application, there will be many more parameters the user can tamper with. As a rule of thumb, _no user input data is secure, until proven otherwise, and every parameter from the user is potentially manipulated_.
 
-Don't be fooled by security by obfuscation and JavaScript security. Developer tools let you review and change every form's hidden fields. _JavaScript can be used to validate user input data, but certainly not to prevent attackers from sending malicious requests with unexpected values_. The Firebug addon for Mozilla Firefox logs every request and may repeat and change them. That is an easy way to bypass any JavaScript validations. And there are even client-side proxies that allow you to intercept any request and response from and to the Internet.
+Don't be fooled by security by obfuscation and JavaScript security. Developer tools let you review and change every form's hidden fields. _JavaScript can be used to validate user input data, but certainly not to prevent attackers from sending malicious requests with unexpected values_. DevTools log every request and may repeat and change them. That is an easy way to bypass any JavaScript validations. And there are even client-side proxies that allow you to intercept any request and response from and to the Internet.
 
 Injection
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