1 files changed, 1 insertions, 1 deletions

diff --git a/plugins/CustomVariables/Reports/GetCustomVariablesValuesFromNameId.php b/plugins/CustomVariables/Reports/GetCustomVariablesValuesFromNameId.php
index 397aa911a8..2e1171af37 100644
--- a/plugins/CustomVariables/Reports/GetCustomVariablesValuesFromNameId.php
+++ b/plugins/CustomVariables/Reports/GetCustomVariablesValuesFromNameId.php
@@ -20,7 +20,7 @@ class GetCustomVariablesValuesFromNameId extends Base
         $this->dimension     = new CustomVariableValue();
         $this->name          = Piwik::translate('CustomVariables_CustomVariables');
         $this->documentation = Piwik::translate('CustomVariables_CustomVariablesReportDocumentation',
-            array('<br />', '<a href="https://matomo.org/docs/custom-variables/" rel="noreferrer"  target="_blank">', '</a>'));
+            array('<br />', '<a href="https://matomo.org/docs/custom-variables/" rel="noreferrer noopener" target="_blank">', '</a>'));
         $this->isSubtableReport = true;
         $this->order = 15;
     }