1 files changed, 2 insertions, 2 deletions
diff --git a/plugins/Referrers/Columns/Base.php b/plugins/Referrers/Columns/Base.php
index 1a86d8f6a0..5064972005 100644
--- a/plugins/Referrers/Columns/Base.php
+++ b/plugins/Referrers/Columns/Base.php
@@ -477,7 +477,7 @@ abstract class Base extends VisitDimension
      */
     protected function getParameterValueFromReferrerUrl($adsenseReferrerParameter)
     {
-        $value = trim(urldecode(UrlHelper::getParameterFromQueryString($this->referrerUrlParse['query'], $adsenseReferrerParameter)));
+        $value = trim(urldecode(UrlHelper::getParameterFromQueryString($this->referrerUrlParse['query'], $adsenseReferrerParameter) ?? ''));
         return $value;
     }
 
@@ -522,7 +522,7 @@ abstract class Base extends VisitDimension
             return false;
         }
 
-        $this->keywordReferrerAnalyzed = mb_strtolower($this->keywordReferrerAnalyzed);
+        $this->keywordReferrerAnalyzed = mb_strtolower($this->keywordReferrerAnalyzed ?? '');
         $this->nameReferrerAnalyzed = mb_strtolower($this->nameReferrerAnalyzed);
         return true;
     }