I don't know about keeping it from showing up at all, but here is how you get ride of it when it does.

Look at Win32::GuiTest. Try the FindWindowLike, ShowWindow, and IsWindowVisible functions:

my @win = FindWindowLike( 0, "Super App", undef );
foreach my $win ( @win ) {
   ShowWindow( $win, SW_HIDE ) if ( IsWindowVisible( $win ) );
}
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