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public_html/lists/admin/upgrade.php

@@ -175,12 +175,14 @@ function output($message)
     // Update jQuery version referenced in public page HTML stored in the database
     if (version_compare($dbversion, '3.4.1', '<')) {
 
+        // The new filename does not hard-code the jQuery version number  
         $replacement = "jquery.min.js";
 
-        // Replace jQuery version in config table.
+        // Replace jQuery version public page footers in config table
         $oldConfigFooter = getConfig('pagefooter');
         $matches = null;
 
+        // Find and replace all references to version-specific jQuery files
         preg_match('/jquery-3.3.1.min.js/', $oldConfigFooter, $matches);
         if ($matches[0] == "jquery-3.3.1.min.js") {
             $pattern = "jquery-3.3.1.min.js";
@@ -197,6 +199,8 @@ function output($message)
         while ($row = Sql_Fetch_Assoc($req)) {
             $footersArray[] = $row['data'];
         }
+
+        // Find and replace all references to version-specific jQuery files
         foreach ($footersArray as $key => $value) {
             preg_match('/jquery-3.3.1.min.js/', $value, $matches);
             if ($matches[0] == "jquery-3.3.1.min.js") {