HTML works, Javascript and HTML events will be stripped at Frontend

In a previos version of this plugin, I was able to build a simple content filter with Javascript manipulating CSS in the category description to set a visual preselection for visitors on the category page.

Now after the Plugin and WordPress are updated (plugin 1.2.3 & WP 5.8.1), the script and the onclick event in buttons placed in the html description are cleaned of the frontend, in the backend everything is fine, the frontend missing passages are saved and shown after reload.

Is there any change in handling of Javascript and HTML events in the newer versions of this plugin or at WordPress?

The Project is not public yet, so I can’t set any access, but I would deliver the content of my Catergory for testing. The Script works, I have tested it in a hardcoded enviroment with the used HTML blocks and CSS.