Changing or appending content of a OOB component.

pp_01 It is technically possible to manipulate OOB components, if it is performant and a good idea in general is the other question, but I know, sometimes there is just no other way...so here you go:

<#-- create a variable that holds the original component's markup -->
<#assing markup>
    <@delegate />
</#assign>

<#-- as $markup basically contains a string of HTML, you can do
        whatever you can with a string and manipulate it... -->
<#-- replace stuff -->
<#assign markup = markup?replace("<RegEx>", "<Replace>", "rmis") />
<#-- regex pattern matching -->
<#assign matches = markup?matches("<RegEx>", "rmis") />
<#if matches>
    <#-- if you have capture groups you can get them with ?groups -->
    <#list matches?groups as match>
        <#-- do something with your match, which will contain all the capture groups as a sequence -->
    </#list>
</#if>

<#-- whenever you are done, just save stuff back to $markup (or any other variable, the name doesn't matter) and output the modded version -->
${markup}