<?xml version="1.0" encoding="UTF-8"?>
<feature-group-spec name="undertow-base" xmlns="urn:jboss:galleon:feature-group:1.0">
    <feature spec="subsystem.undertow">
        <param name="statistics-enabled" value="${wildfly.undertow.statistics-enabled:${wildfly.statistics-enabled:false}}" />

        <feature spec="subsystem.undertow.buffer-cache">
            <param name="buffer-cache" value="default" />
        </feature>
        <feature spec="subsystem.undertow.configuration.filter"/>
        <feature spec="subsystem.undertow.configuration.handler"/>
        <feature spec="subsystem.undertow.server">
            <param name="server" value="default-server" />
            <feature spec="subsystem.undertow.server.host">
                <param name="host" value="default-host" />
                <param name="alias" value="[localhost]"/>
            </feature>
            <feature spec="subsystem.undertow.server.http-listener">
                <param name="socket-binding" value="http"/>
                <param name="http-listener" value="default"/>
                <param name="enable-http2" value="true"/>
                <unset param="worker"/>
                <unset param="buffer-pool"/>
                <param name="redirect-socket" value="https" />
            </feature>
        </feature>
        <feature spec="subsystem.undertow.servlet-container">
            <param name="servlet-container" value="default" />
        </feature>
    </feature>
</feature-group-spec>

<?xml version="1.0" encoding="UTF-8"?>
<feature-group-spec name="undertow-base" xmlns="urn:jboss:galleon:feature-group:1.0">
    <feature spec="subsystem.undertow">
        <param name="statistics-enabled" value="${wildfly.undertow.statistics-enabled:${wildfly.statistics-enabled:false}}" />

        <feature spec="subsystem.undertow.buffer-cache">
            <param name="buffer-cache" value="default" />
        </feature>
        <feature spec="subsystem.undertow.byte-buffer-pool">
            <param name="byte-buffer-pool" value="default" />
        </feature>
        <feature spec="subsystem.undertow.configuration.filter"/>
        <feature spec="subsystem.undertow.configuration.handler"/>
        <feature spec="subsystem.undertow.server">
            <param name="server" value="default-server" />
            <feature spec="subsystem.undertow.server.host">
                <param name="host" value="default-host" />
                <param name="alias" value="[localhost]"/>
            </feature>
            <feature spec="subsystem.undertow.server.http-listener">
                <param name="socket-binding" value="http"/>
                <param name="http-listener" value="default"/>
                <param name="enable-http2" value="true"/>
                <unset param="worker"/>
                <unset param="buffer-pool"/>
                <param name="redirect-socket" value="https" />
            </feature>
        </feature>
        <feature spec="subsystem.undertow.servlet-container">
            <param name="servlet-container" value="default" />
        </feature>
    </feature>
</feature-group-spec>

Update BufferPool to use Undertow's ByteBufferPool rather than XNIO's
[WFLY-16711] Update BufferPool to use Undertow's ByteBufferPool rather than XNIO's

Update WildFly Core version to get buffer-pool removal
Update feature-group to define new byte-buffer-pool
