diff --git a/scripts/overview.php b/scripts/overview.php
index 2f55b52..0132566 100644
--- a/scripts/overview.php
+++ b/scripts/overview.php
@@ -506,6 +506,7 @@ function generateMiniGraph(elem, comname) {
       // Create a div element for the chart window
       if (typeof(window.chartWindow) != 'undefined') {
         document.body.removeChild(window.chartWindow);
+        window.chartWindow = undefined;
       }
       var chartWindow = document.createElement('div');
       chartWindow.className = "chartdiv"
@@ -615,6 +616,7 @@ function generateMiniGraph(elem, comname) {
       closeButton.style.right = '5px';
       closeButton.addEventListener('click', function() {
         document.body.removeChild(chartWindow);
+        window.chartWindow = undefined;
       });
       chartWindow.appendChild(closeButton);
       window.chartWindow = chartWindow;
@@ -631,6 +633,7 @@ window.addEventListener('scroll', function() {
   // Loop through all chart elements and remove them
   charts.forEach(function(chart) {
     chart.parentNode.removeChild(chart);
+    window.chartWindow = undefined;
   });
 });