double connection db mysql error

phprunner 8.1 enterprise build 25268 x64
i have 2 connections to 2 mysql db,1st in localhost and the 2nd in another server.

after login all is ok, all tables of localhost db are visible, i switch to a table of second connection and it's ok, but now if i try to reopen a table from 1st connection (firmedigitali in localhost) this is the error:
Fatal error: Unknown database 'firmedigitali' in C:\sitiweb\webpub\firmedigitali\connections\MySQLiConnection.php on line 89
and now i have to close the browser (ie 11 o firefox is the same) to log in again.
have any idea ?

thanks
Fabio