Internal: Keep in session variable for user selected locale - refs BT#21304

src/CoreBundle/EventListener/LogoutListener.php

@@ -43,6 +43,7 @@ class LogoutListener
         $request = $event->getRequest();
 
         // Chamilo logout
+        $request->getSession()->remove('_selected_locale');
         $request->getSession()->remove('_locale');
         $request->getSession()->remove('_locale_user');
 

src/CoreBundle/EventSubscriber/LocaleSubscriber.php

@@ -54,7 +54,7 @@ class LocaleSubscriber implements EventSubscriberInterface
         $sessionHandler = $request->getSession();
 
         if ($attrLocale = $request->query->get('_locale')) {
-            $sessionHandler->set('_locale', $attrLocale);
+            $sessionHandler->set('_selected_locale', $attrLocale);
         }
 
         $locale = $this->getCurrentLanguage($request);
@@ -91,7 +91,7 @@ class LocaleSubscriber implements EventSubscriberInterface
         }
 
         // 4. force locale if it was selected from the URL
-        if ($localeFromUrl = $sessionHandler->get('_locale')) {
+        if ($localeFromUrl = $sessionHandler->get('_selected_locale')) {
             $localeList['user_selected_lang'] = $localeFromUrl;
         }