Disable auto html code in ckeditor 5

Problem/Motivation

In CKEditor 4 we had the ACF - Advanced Content Filter, which filters incoming HTML content by transforming and removing elements, attributes, classes and styles that are not allowed. This could be disabled in order not to modify the HTML of a basic page, for example.

I am having difficulty doing this in CKEditor 5 because every time I insert an <i> tag for Font Awesome on a basic HTML page using the full HTML format, CKEditor 5 adds a parent <em> element.

This greatly impacts the CSS of my theme. How can I prevent and stop this? I want the editor to respect and not interfere with my HTML code.

All full HTML filter settings are following the Drupal default.

Thank you!