since the open forms has changed to bottom of screen you can no longer have multiple forms open at the same time unless you edit the main program window size (ie not maximised) client has just upgraded from 2011 to 2017 and finds this an inconvenience
Please can you clarify what you mean, are you referring to the lists appearing as unique blocks on the bottom screen section or the open windows dialogue?
Would also be good to understand the reason your looking for the functionality and the benefit it will bring.