Add request param to primefaces advanced fileupload

Question

I am trying to add a request parameter to an advanced primefaces p:fileUpload. I try to do this in order to check for this parameter in a Servlet.Filter. Using f:param with a simple p:fileUpload mode="simple" works fine:

<h:form enctype="multipart/form-data">
    <p:fileUpload value="#{myBean.file}" mode="simple" skinSimple="true"/>
    <p:commandButton value="Submit" ajax="true" action="#{myBean.upload}">
        <f:param name="doStuffInFilter" value="true"/>
    </p:commandButton>
</h:form>

However, i can not get this to work with the p:fileUpload mode="advanced" Component to work:

<h:form enctype="multipart/form-data">
    <p:fileUpload id="fileUploadPrimefaces1" listener="#{myBean.handleFileUpload}" 
                  mode="advanced" dragDropSupport="true" ... />
</h:form>

What i tried:

1. Add f:param to p:fileUpload -> does not seem to have any effect
2. Based on this Stackoverflow Answer, I tried to add the param to the request using the Primefaces ClientAPI like this:

<p:fileUpload mode="advanced" ... onstart="this.cfg.ext={params: [name: 'doStuffInFilter', value: 'true']}" />

While I could see that the value was set using the browser dev tools, the HttpServletRequest did not contain the parameter on serverSide. Do you have any Idea how to solve this?