I have installed plug_cbantispam_2.0.0+build.2016.12.30.01.41.44.878e01ca2. I have enabled it and the two fields antispam_captcha and antispam_ipaddress.
When I click on the plugin in Community Builder -> Plugin -> CB AntiSpam I get a 500 Internal Server Error:
Fatal error: Call to undefined function imagettfbbox() in .../web/components/com_comprofiler/plugin/user/plug_cbantispam/cbantispam.php on line 754
I'm using CB v. 2.1.2 (default install, no customisation), Joomla 3.6.5 fully updated (new install). Standard captcha in global configuration is not set and Joomla plugin Captcha - ReCaptcha is deactivated. I am using the Protostar template for testing purpose. I'm using PHP 5.6.
For testing purpose I have tried to update CB to v. 2.1.2+build.2017.02.08.01.14.28.ec3d63d1f. Same error.
Anybody have an idea what I am missing here?