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@@ -480,6 +480,7 @@ Only main chapters:
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://www.robtex.com/"><b>Robtex</b></a> - uses various sources to gather public information about IP numbers, domain names, host names, routes etc.<br>
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://securitytrails.com/"><b>Security Trails</b></a> - APIs for Security Companies, Researchers and Teams.<br>
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://tools.keycdn.com/curl"><b>Online Curl</b></a> - curl test, analyze HTTP Response Headers.<br>
+&nbsp;&nbsp;:small_orange_diamond: <a href="https://extendsclass.com/"><b>Online Tools for Developers</b></a> - HTTP API tools, testers, encoders, converters, formatters, and other tools.<br>
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://ping.eu/"><b>Ping.eu</b></a> - online Ping, Traceroute, DNS lookup, WHOIS and others.<br>
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://network-tools.com/"><b>Network-Tools</b></a> - network tools for webmasters, IT technicians & geeks.<br>
 &nbsp;&nbsp;:small_orange_diamond: <a href="https://riseup.net/"><b>Riseup</b></a> - provides online communication tools for people and groups working on liberatory social change.<br>