See also CR 6643769.

Short desc:
User run the Applet on main page, and then he pop up windows which run Applet also. When the main page is refreshed automatically, the main page steal focus from the pop up windows.

MR 1.4.2_23 for CR 6643769 fixes this issue for 1.4.2_23 + IE,
problem still actual for 1.4.2_23/24 + Firefox ( 2.0, 3.5.1 ) on windows.

All works correctly for 6u16 + Firefox ( initial_focus=true, initial_focus=false )
                and for 5u21 + Firefox ( for applet param initial_focus=false only )

For 1.4.2_23/24 focus stealing depends on initial_focus param:
 - for initial_focus=false focus moved to the main windiw
 - for initial_focus=true focus stealed from second ( active ) window, but not set on  
   main window.

See "Comments" section for more info and steps to reproduce.