the reason why i asked that is simple, browser windows (if they are not opened seperately) will share cookie info.
e.g.:
browser window 1 is opened, Ctrl+N is used to open window 2.
any changes in the session in window2 will now affect window 1.
try opening 2 browser windows (using the browser icon itself) and try logging in with the users. the 2 sessions of VS is not required...
Known is handfull, Unknown is worldfull