PSR-12 isn't an active PSR anymore. Don't list it on the main page.

Author: kenguest

source/index.twig

@@ -133,7 +133,6 @@ interface RequestInterface extends MessageInterface
                     <ul class="home_features__links">
                         <li><a class="home_features__link" href="/per/coding-style/">PER Coding Style</a></li>
                         <li><a class="home_features__link" href="/psr/psr-1/">PSR-1: Basic Coding Standard</a></li>
-                        <li><a class="home_features__link" href="/psr/psr-12/">PSR-12: Extended Coding Style Guide</a></li>
                     </ul>
                 </div>
                 <div class="home_features__editor">