Changing companies opens IE window with EP

Hi,

Whenever a user changes company in AX 2012, IE opens a new window with the enterprise portal in it. Is there a setting somewhere to switch this option off? I've looked at what happens in the SysDataAreaSelect Form but no clues there, it seems to be triggered only after the form closes.

Also strangely this happens only when changing companies in an existing workspace, not when you click "new workspace" or when you change compabies in the IDE.

Does anybody know more about how this works and how we can turn it off?