http://bugs.winehq.org/show_bug.cgi?id=12353
--- Comment #6 from Giuseppe Bilotta giuseppe.bilotta@gmail.com 2008-04-05 08:48:23 --- No, I can't confirm that this is what Windows does.
Some more testing has shown an interesting additional tidbit: if from the systray I select 'minimize' and then 'restore', the Bat's main window shows again.
I will look at the thing some more.
(Can somebody please at least 'confirm' the bug? shoud it be marked as dupe of 12264?)