Web: Register hooks provided by the app when bootstrapping

library/Icinga/Application/Web.php

@@ -6,6 +6,7 @@ namespace Icinga\Application;
 require_once __DIR__ . '/EmbeddedWeb.php';
 
 use ErrorException;
+use Icinga\Application\ProvidedHook\LessVarsLoader;
 use ipl\I18n\GettextTranslator;
 use ipl\I18n\Locale;
 use ipl\I18n\StaticTranslator;
@@ -101,7 +102,8 @@ class Web extends EmbeddedWeb
             ->setupUser()
             ->setupTimezone()
             ->setupInternationalization()
-            ->setupFatalErrorHandling();
+            ->setupFatalErrorHandling()
+            ->registerApplicationHooks();
     }
 
     /**
@@ -461,6 +463,18 @@ class Web extends EmbeddedWeb
         return $this;
     }
 
+    /**
+     * Register all hooks provided by the main application
+     *
+     * @return $this
+     */
+    protected function registerApplicationHooks()
+    {
+        Hook::register('Themebuilder\\LessVarsLoader', LessVarsLoader::class, LessVarsLoader::class);
+
+        return $this;
+    }
+
     /**
      * (non-PHPDoc)
      * @see ApplicationBootstrap::detectTimezone() For the method documentation.