This is something new I came across thanks to a colleague; that I thought would be good to share.

Recently I had an issue where I needed to hide the standard UCM header and footer, but allow the users to navigate through the links available on the body.
(This  process will also allow you to persist other params)

If you add the parameter coreContentOnly=1 like this –

http://contentServer/cs/idcplg?IdcService=GET_DOC_PAGE&Action=GetTemplatePage
&Page=HOME_PAGE&coreContentOnly=1 

The header/footer are removed leaving the body content available however on navigating selecting a link or interacting with a form field the coreContentOnly param is removed therefore displaying the header & footer on the next page.

In the past I’ve written components to handle this or done some magic on the web-server; however no more is this needed!
There is a workaround to persist parameters –

By placing /_p/ after the ISAPI/CGI file Name (usually idcplg) – you can apply and persist variables.

http://contentServer/cs/idcplg/_p/?IdcService=…

This variable mapping can be found by opening the PersistentUrlKeys table.

Here are some of the mappings – 

min =coreContentOnly
cc = ClientControl

So to enable coreContentOnly=1 throughout you can use either approach –

http://contentServer/cs/idcplg/_p/min?IdcService=…

or

http://contentServer/cs/idcplg/_p/min-1?IdcService=…

On the first one I did not set -1 as 1 is the default assumed value the dash is used as a seperator for key/value.
If I wanted to add ClientControl or another variable I  can add the mapping in like this –

http://contentServer/cs/idcplg/_p/min/cc-queryselect?IdcService=…

Important – this mapping must exist in Content Server the SCRIPT_NAME environment variable or it will not be persisted.