adjust to changes on main, fixes #33

lib/Controller.php

@@ -10,15 +10,18 @@ namespace TracToGitlab;
  */
 abstract class Controller extends \PluginController
 {
-    public function __get($offset)
+    public function &__get($offset)
     {
-        $container = $this->plugin->getDIContainer();
+        $result = &parent::__get($offset);
 
-        if (!isset($container[$offset])) {
-            return $this->$offset ?? null;
+        if ($result === null) {
+            $container = $this->plugin->getDIContainer();
+            if (isset($container[$offset])) {
+                return $container[$offset];
+            }
         }
 
-        return $container[$offset];
+        return $result;
     }
 
     protected function activateNavigation(string ...$path): void