chore(@mendix/html-element-web): update changelog

Author: uicontent

packages/pluggableWidgets/html-element-web/CHANGELOG.md

@@ -6,6 +6,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 ## [Unreleased]
 
+## [1.2.6] - 2026-03-31
+
 ### Security
 
 - Updated dompurify library to version 3.3.3 to incorporate latest improvements and security fixes.