core/modules/forum/src/Controller/ForumController.php | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/core/modules/forum/src/Controller/ForumController.php b/core/modules/forum/src/Controller/ForumController.php
index aeb172c..f0ea9b3 100644
--- a/core/modules/forum/src/Controller/ForumController.php
+++ b/core/modules/forum/src/Controller/ForumController.php
@@ -167,8 +167,8 @@ public function forumPage(TermInterface $taxonomy_term) {
       $header = $build['header'];
     }
     else {
-      $topics = '';
-      $header = array();
+      $topics = [];
+      $header = [];
     }
     return $this->build($taxonomy_term->forums, $taxonomy_term, $topics, $taxonomy_term->parents, $header);
   }
@@ -232,10 +232,8 @@ protected function build($forums, TermInterface $term, $topics = array(), $paren
     foreach ($forums as $forum) {
       $this->renderer->addCacheableDependency($build, $forum);
     }
-    if (!empty($topics)) {
-      foreach ($topics as $topic) {
-        $this->renderer->addCacheableDependency($build, $topic);
-      }
+    foreach ($topics as $topic) {
+      $this->renderer->addCacheableDependency($build, $topic);
     }
     foreach ($parents as $parent) {
       $this->renderer->addCacheableDependency($build, $parent);