It is used to allow template designers to change the default engine resource bundle used by engine popups opened from pages using this template on a per user basis. This therefore enables for different popups styles for given users. This tag should be called on top of the template JSP file.
Please refer to the 'Engine Popup Customization' documentation for more details.
Example :
<content:setUsrEngineResourceBundle resourceBundle="albertResource" userName="albert" />
where albertResource is the name of Resource Bundle file for the user "albert" so that we get albertResource.properties .