Fixed JS issue in Key => Value pairs when changing existing key name (#2539)

CHANGELOG.md

@@ -10,6 +10,7 @@
         - PHP 7.4: implemented required `Stream::stream_set_option()` method for streams
         - PHP 7.4: Fixed twig rendering errors (#2613)
         - PHP 7.4: Fixed modifying particle settings throws an error (#2631)
+        - Fixed JS issue in Key => Value pairs when changing existing key name (#2539)
         - Fixed grid breakpoint calculation overlaps not being tight enough (#2492)
         - Helium: Headings should use title font instead of default (#2599)
 1. [Joomla](#joomla)

platforms/common/application/particles/keyvalue/index.js

@@ -122,7 +122,9 @@ ready(function() {
         if (keyElement == element) {
             // renamed or cleared key, need to cleanup JSON
             if (key !== keyValue && !duplicate) {
-                data.splice(index, 1);
+                if(typeof data[index] !== 'undefined') {
+                    delete data[index][key];
+                }
                 keyElement.data('keyvalue-key', keyValue || '');
             }