The default character encoding defined in web.xml is not taking effect

Issue

In web.xml, <request-character-encoding> and <response-character-encoding> introduced in Servlet 4.0 are not working on JBoss EAP:

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="https://jakarta.ee/xml/ns/jakartaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="https://jakarta.ee/xml/ns/jakartaee
                      https://jakarta.ee/xml/ns/jakartaee/web-app_6_0.xsd"
         version="6.0">
    <request-character-encoding>UTF-8</request-character-encoding>
    <response-character-encoding>UTF-8</response-character-encoding>
<web-app>